Dissertations / Theses: 'Sequential behaviors'

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Ma, Liya. "Coding of sequential behaviors by anterior cingulate cortex ensembles." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/48442.

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The anterior cingulate cortex (ACC) has been implicated in a myriad of different functions. Converging evidence suggests that the ACC continuously monitors and evaluates actions and their consequences. Such functions are essential in representing action sequences which are the building blocks of all complex behaviors. This dissertation seeks to delineate how ACC neuronal ensembles represent different types of information with special emphasis on action sequences. Chapter 2 shows that the ACC ensembles represents different action sequences via unique activity patterns that change if the order of the actions are altered or if the locations of the actions is changed. Interestingly such shifts are achieved when overall levels of activity remain fixed. Chapter 3 reveals a very different arrangement in which progression through a sequence of actions towards a goal is associated with a change in the overall level of neural activity without a significant change in the patterns of activity. Specifically, ACC ensembles display a smooth progressive change in overall activity over three lever press actions that culminate in a reward. In contrast, the dorsal striatal (DS) ensembles recorded simultaneously from the same animals display fluctuations in activity level that are tightly linked to each action. Together these two chapters show that the ACC may use two different firing rate-related codes to convey categorical versus continuous forms of information. Chapter 4 provides a further examination of the mechanisms which allows the ACC ensembles to encode multiple types of categorical information. While the DS neurons encode both the sequence and the location of the levers in a somewhat synchronized fashion, ACC neurons encoded both of these types of information but kept them functionally segregated. As a result, even though ACC single neurons were no better than the DS in sequence decoding, sequence decoding by ACC ensembles was far superior to DS ensembles. The last chapter attempts to produce a unified theory of ACC function based on its coding properties. I will argue that the ACC monitors many aspects of experience while evaluating the current state with reference to a goal. Its multiple coding schemes efficiently serve both monitoring and evaluating functions.
Medicine, Faculty of
Graduate

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Floehr, Sophia H. "Code-Mixing Behaviors of Sequential Spanish-English Bilingual Children: An Exploratory Study." Bowling Green State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1587140326261896.

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Hoffman, Mary Kathryn. "Physiochemical behaviors of radiocesium in a calciferous, post-detonation environment." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1584015906269554.

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Taylor, Kendra C. "Sequential Auction Design and Participant Behavior." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7250.

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This thesis studies the impact of sequential auction design on participant behavior from both a theoretical and an empirical viewpoint. In the first of the two analyses, three sequential auction designs are characterized and compared based on expected profitability to the participants. The optimal bid strategy is derived as well. One of the designs, the alternating design, is a new auction design and is a blend of the other two. It assumes that the ability to bid in or initiate an auction is given to each side of the market in an alternating fashion to simulate seasonal markets. The conditions for an equilibrium auction design are derived and characteristics of the equilibrium are outlined. The primary result is that the alternating auction is a viable compromise auction design when buyers and suppliers disagree on whether to hold a sequence of forward or reverse auctions. We also found the value of information on future private value for a strategic supplier in a two-period case of the alternating and reverse auction designs. The empirical work studies the cause of low aggregation of timber supply in reverse auctions of an online timber exchange. Unlike previous research results regarding timber auctions, which focus on offline public auctions held by the U.S. Forest Service, we study online private auctions between logging companies and mills. A limited survey of the online auction data revealed that the auctions were successful less than 50% of the time. Regression analysis is used to determine which internal and external factors to the auction affect the aggregation of timber in an effort to determine the reason that so few auctions succeeded. The analysis revealed that the number of bidders, the description of the good and the volume demanded had a significant influence on the amount of timber supplied through the online auction exchange. A plausible explanation for the low aggregation is that the exchange was better suited to check the availability for custom cuts of timber and to transact standard timber.

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Raffensperger, Peter Abraham. "Measuring and Influencing Sequential Joint Agent Behaviours." Thesis, University of Canterbury. Electrical and Computer Engineering, 2013. http://hdl.handle.net/10092/7472.

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Algorithmically designed reward functions can influence groups of learning agents toward measurable desired sequential joint behaviours. Influencing learning agents toward desirable behaviours is non-trivial due to the difficulties of assigning credit for global success to the deserving agents and of inducing coordination. Quantifying joint behaviours lets us identify global success by ranking some behaviours as more desirable than others. We propose a real-valued metric for turn-taking, demonstrating how to measure one sequential joint behaviour. We describe how to identify the presence of turn-taking in simulation results and we calculate the quantity of turn-taking that could be observed between independent random agents. We demonstrate our turn-taking metric by reinterpreting previous work on turn-taking in emergent communication and by analysing a recorded human conversation. Given a metric, we can explore the space of reward functions and identify those reward functions that result in global success in groups of learning agents. We describe 'medium access games' as a model for human and machine communication and we present simulation results for an extensive range of reward functions for pairs of Q-learning agents. We use the Nash equilibria of medium access games to develop predictors for determining which reward functions result in turn-taking. Having demonstrated the predictive power of Nash equilibria for turn-taking in medium access games, we focus on synthesis of reward functions for stochastic games that result in arbitrary desirable Nash equilibria. Our method constructs a reward function such that a particular joint behaviour is the unique Nash equilibrium of a stochastic game, provided that such a reward function exists. This method builds on techniques for designing rewards for Markov decision processes and for normal form games. We explain our reward design methods in detail and formally prove that they are correct.

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Farooqui, Ausaf Ahmed. "Fronto-parietal cortex in sequential behaviour." Thesis, University of Cambridge, 2012. https://www.repository.cam.ac.uk/handle/1810/243944.

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This dissertation investigates the fronto-parietal representation of the structure of organised mental episodes by studying its effect on the representation of cognitive events occurring at various positions within it. The experiments in chapter 2 look at the completion of hierarchically organized mental (task/subtask) episodes. Multiple identical target-detection events were organized into a sequential task episode, and the individual events were connected in a means-to-end relationship. It is shown that events that are conceptualized as completing defined task episodes elicit greater activity compared to identical events lying within the episode; the magnitude of the end of episode activity depended on the hierarchical abstraction of the episode. In chapter 3, the effect of ordinal position of the cognitive events, making up the task episode, on their representation is investigated in the context of a biphasic task episode. The design further manipulated the cognitive load of the two phases independently. This allowed for a direct comparison of the effect of phase vis-à-vis the effect of cognitive load. The results showed that fronto-parietal regions that increased their activity in response to cognitive load, also increased their activity for the later phases of the task episode, even though the cognitive load associated with the later phase was, arguably, lower than the previous phase. Chapter 4 investigates if the characteristics of the higher-level representations, like organization of task descriptions, have a causal role in determining the structure of the ensuing mental episode. Results show this to be true. They also confirm the results of earlier chapters in a different framework. Chapter 5 shows that the effect of episode structure is not limited to the elicited activity, but also affects the information content of the representation of the events composing the episode. Specifically, the information content in many regions of later steps is higher than that of earlier steps. Together, the results show widespread representation of the structure of organised mental episodes.

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Henderson, Stacee Lyn. "Sequential cattle and sheep grazing for Spotted Knapweed control." Thesis, Montana State University, 2008. http://etd.lib.montana.edu/etd/2008/henderson/HendersonS1208.pdf.

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Spotted knapweed (Centaurea stoebe L.) infests millions of hectares of native rangeland in North America. Spotted knapweed creates large monocultures, which decreases biodiversity, reduces livestock and wildlife forage, and increases surface water runoff and soil erosion. Sheep are an effective tool for controlling spotted knapweed and have been widely used on cattle ranches for weed control. However, cattle producers are concerned that sheep will over-utilize desirable graminoids. Therefore, research is needed to determine an effective grazing strategy using cattle and sheep that will adversely affect spotted knapweed, while minimizing over-use of desirable graminoids across the landscape. This 2-year study quantified graminoid and spotted knapweed utilization and diet composition and foraging behavior of cattle and sheep sequentially grazing spotted knapweed-infested rangeland in western Montana. Twenty-one Targhee yearling wethers and 9 Black Angus yearling cattle were used. Animals were randomly assigned to one of 3, 0.81-ha pastures that were grazed in either mid-June or mid-July (n=6 pastures). Cattle grazed each pasture for 7 days, immediately followed by sheep grazing for 7 days in each month. Analysis of covariance was used to determine differences in diets, relative preference indices, foraging behavior, and utilization between June and July for cattle and sheep to determine the optimal month for implementing prescribed sheep grazing. Relative utilization of spotted knapweed did not differ between June and July and averaged 61.5%. Graminoid utilization was moderate (<45%). Cattle preferred forbs in June, spotted knapweed and forbs in July, and avoided graminoids in July. Sheep avoided graminoids in June and July, preferred forbs in June, and showed no preference or avoidance of spotted knapweed. Cattle ranches with large spotted knapweed infestations can effectively use prescribed sheep grazing immediately following cattle grazing in June or July to achieve high levels of use on spotted knapweed, thus reducing viable seeds incorporated into the soil, while maintaining optimal utilization levels on desirable graminoids.

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Gautrais, Clément. "Signatures : detecting and characterizing complex recurrent behavior in sequential data." Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1S041/document.

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Cette thèse introduit un nouveau type de motif appelé signature. La signature segmente une séquence d'itemsets, afin de maximiser la taille de l'ensemble d'items qui apparaît dans tous les segments. La signature a été initialement introduite pour identifier les produits favoris d'un consommateur de supermarché à partir de son historique d'achat. L'originalité de la signature vient du fait qu'elle identifie les items récurrents qui 1) peuvent apparaître à différentes échelles temporelles, 2) peuvent avoir des occurrences irrégulières et 3) peuvent être rapidement compris par des analystes. Étant donné que les approches existantes en fouille de motifs n'ont pas ces 3 propriétés, nous avons introduit la signature. En comparant la signature avec les méthodes de l'état de l'art, nous avons montré que la signature est capable d'identifier de nouvelles régularités dans les données, tout en identifiant les régularités détectées par les méthodes existantes. Bien qu'initialement liée au domaine de la fouille de motifs, nous avons également lié le problème de la fouille de signatures au domaine de la segmentation de séquences. Nous avons ensuite défini différents algorithmes, utilisant des méthodes liées à la fouille de motifs et à la segmentation de séquences. Les signatures ont été utilisées pour analyser un large jeu de données issu d'un supermarché français. Une analyse qualitative des signatures calculées sur ces consommateurs réels a montré que les signatures sont capables d'identifier les produits favoris d'un consommateur. Les signatures ont également été capables de détecter et de caractériser l'attrition de consommateurs. Cette thèse définit également 2 extensions de la signature. La première extension est appelée la sky-signature. La sky-signature permet de présenter les items récurrents d'une séquence à différentes échelles de temps. La sky-signature peut être vue comme une manière efficace de résumer les signatures calculées à toutes les échelles de temps possibles. Les sky-signatures ont été utilisées pour analyser les discours de campagne des candidats à la présidentielle américaine de 2016. Les sky-signatures ont identifié les principaux thèmes de campagne de chaque candidat, ainsi que leur rythme de campagne. Cette analyse a également montré que les signatures peuvent être utilisées sur d'autres types de jeux de données. Cette thèse introduit également une deuxième extension de la signature, qui permet de calculer la signature qui correspond le plus aux données. Cette extension utilise une technique de sélection de modèle basée sur le principe de longueur de description minimale, communément utilisée en fouille de motifs. Cette extension a également été utilisée pour analyser des consommateurs de supermarché
Cette thèse introduit un nouveau type de motif appelé signature. La signature segmente une séquence d'itemsets, afin de maximiser la taille de l'ensemble d'items qui apparaît dans tous les segments. La signature a été initialement introduite pour identifier les produits favoris d'un consommateur de supermarché à partir de son historique d'achat. L'originalité de la signature vient du fait qu'elle identifie les items récurrents qui 1) peuvent apparaître à différentes échelles temporelles, 2) peuvent avoir des occurrences irrégulières et 3) peuvent être rapidement compris par des analystes. Étant donné que les approches existantes en fouille de motifs n'ont pas ces 3 propriétés, nous avons introduit la signature. En comparant la signature avec les méthodes de l'état de l'art, nous avons montré que la signature est capable d'identifier de nouvelles régularités dans les données, tout en identifiant les régularités détectées par les méthodes existantes. Bien qu'initialement liée au domaine de la fouille de motifs, nous avons également lié le problème de la fouille de signatures au domaine de la segmentation de séquences. Nous avons ensuite défini différents algorithmes, utilisant des méthodes liées à la fouille de motifs et à la segmentation de séquences. Les signatures ont été utilisées pour analyser un large jeu de données issu d'un supermarché français. Une analyse qualitative des signatures calculées sur ces consommateurs réels a montré que les signatures sont capables d'identifier les produits favoris d'un consommateur. Les signatures ont également été capables de détecter et de caractériser l'attrition de consommateurs. Cette thèse définit également 2 extensions de la signature. La première extension est appelée la sky-signature. La sky-signature permet de présenter les items récurrents d'une séquence à différentes échelles de temps. La sky-signature peut être vue comme une manière efficace de résumer les signatures calculées à toutes les échelles de temps possibles. Les sky-signatures ont été utilisées pour analyser les discours de campagne des candidats à la présidentielle américaine de 2016. Les sky-signatures ont identifié les principaux thèmes de campagne de chaque candidat, ainsi que leur rythme de campagne. Cette analyse a également montré que les signatures peuvent être utilisées sur d'autres types de jeux de données. Cette thèse introduit également une deuxième extension de la signature, qui permet de calculer la signature qui correspond le plus aux données. Cette extension utilise une technique de sélection de modèle basée sur le principe de longueur de description minimale, communément utilisée en fouille de motifs. Cette extension a également été utilisée pour analyser des consommateurs de supermarché

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Smith, Denise P. A. "The Basal Ganglia and Sequential Learning." Kent State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=kent1353430597.

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ISHII, Katsuya, Hiroaki TAKADA, Shinya HONDA, Hiroyuki TOMIYAMA, and Yuko HARA. "Function-Level Partitioning of Sequential Programs for Efficient Behavioral Synthesis." Institute of Electronics, Information and Communication Engineers, 2007. http://hdl.handle.net/2237/15031.

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Lonjarret, Corentin. "Sequential recommendation and explanations." Thesis, Lyon, 2021. http://theses.insa-lyon.fr/publication/2021LYSEI003/these.pdf.

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Ces dernière années, les systèmes de recommandation ont reçu beaucoup d'attention avec l'élaboration de nombreuses propositions qui tirent parti des nouvelles avancées dans les domaines du Machine Learning et du Deep Learning. Grâce à l'automatisation de la collecte des données des actions des utilisateurs tels que l'achat d'un objet, le visionnage d'un film ou le clic sur un article de presse, les systèmes de recommandation ont accès à de plus en plus d'information. Ces données sont des retours implicites des utilisateurs (appelé «~implicit feedback~» en anglais) et permettent de conserver l'ordre séquentiel des actions de l’utilisateur. C'est dans ce contexte qu'ont émergé les systèmes de recommandations qui prennent en compte l’aspect séquentiel des données. Le but de ces approches est de combiner les préférences des utilisateurs (le goût général de l’utilisateur) et la dynamique séquentielle (les tendances à court terme des actions de l'utilisateur) afin de prévoir la ou les prochaines actions d'un utilisateur. Dans cette thèse, nous étudions la recommandation séquentielle qui vise à prédire le prochain article/action de l'utilisateur à partir des retours implicites des utilisateurs. Notre principale contribution, REBUS, est un nouveau modèle dans lequel seuls les items sont projetés dans un espace euclidien d'une manière qui intègre et unifie les préférences de l'utilisateur et la dynamique séquentielle. Pour saisir la dynamique séquentielle, REBUS utilise des séquences fréquentes afin de capturer des chaînes de Markov d'ordre personnalisé. Nous avons mené une étude empirique approfondie et démontré que notre modèle surpasse les performances des différents modèles de l’état de l’art, en particulier sur des jeux de données éparses. Nous avons également intégré REBUS dans myCADservices, une plateforme collaborative de la société française Visiativ. Nous présentons notre retour d'expérience sur cette mise en production du fruit de nos travaux de recherche. Enfin, nous avons proposé une nouvelle approche pour expliquer les recommandations fournies aux utilisateurs. Le fait de pouvoir expliquer une recommandation permet de contribuer à accroître la confiance qu'un utilisateur peut avoir dans un système de recommandation. Notre approche est basée sur la découverte de sous-groupes pour fournir des explications interprétables d'une recommandation pour tous types de modèles qui utilisent comme données d’entrée les retours implicites des utilisateurs
Recommender systems have received a lot of attention over the past decades with the proposal of many models that take advantage of the most advanced models of Deep Learning and Machine Learning. With the automation of the collect of user actions such as purchasing of items, watching movies, clicking on hyperlinks, the data available for recommender systems is becoming more and more abundant. These data, called implicit feedback, keeps the sequential order of actions. It is in this context that sequence-aware recommender systems have emerged. Their goal is to combine user preference (long-term users' profiles) and sequential dynamics (short-term tendencies) in order to recommend next actions to a user. In this thesis, we investigate sequential recommendation that aims to predict the user's next item/action from implicit feedback. Our main contribution is REBUS, a new metric embedding model, where only items are projected to integrate and unify user preferences and sequential dynamics. To capture sequential dynamics, REBUS uses frequent sequences in order to provide personalized order Markov chains. We have carried out extensive experiments and demonstrate that our method outperforms state-of-the-art models, especially on sparse datasets. Moreover we share our experience on the implementation and the integration of REBUS in myCADservices, a collaborative platform of the French company Visiativ. We also propose methods to explain the recommendations provided by recommender systems in the research line of explainable AI that has received a lot of attention recently. Despite the ubiquity of recommender systems only few researchers have attempted to explain the recommendations according to user input. However, being able to explain a recommendation would help increase the confidence that a user can have in a recommendation system. Hence, we propose a method based on subgroup discovery that provides interpretable explanations of a recommendation for models that use implicit feedback

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Takahashi, Toshihiro, Tatsuji Yamada, Naoki Hayakawa, and Hitoshi Okubo. "Space charge behavior in SF6 gas and sequential generation of PD pulses." IEEE, 2000. http://hdl.handle.net/2237/6757.

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Nowacek, Douglas Paul. "Sound use, sequential behavior and ecology of foraging bottlenose dolphins, Tursiops truncatus." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/85611.

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Thesis (Ph. D.)--Joint Program in Biological Oceanography (Massachusetts Institute of Technology, Dept. of Biology; and the Woods Hole Oceanographic Institution), 1999.
Includes bibliographical references.
Odontocetes are assumed to use echolocation for navigation and foraging, but neither of these uses of biosonar has been conclusively demonstrated in free-ranging animals. Many bats are known to use echolocation throughout foraging sequences, changing the structure and timing of clicks as they progress towards prey capture. For odontocetes, however, we do not know enough about their foraging behavior to describe such sequences. To conduct detailed behavioral observations of any subject animal, the observer must be able to maintain continuous visual contact with the subject for a period commensurate with the duration of the behavior(s) of interest. Behavioral studies of cetaceans, which spend approximately 95% of their time below the water's surface, have been limited to sampling surface behavior except in special circumstances, e.g. clear-water environments, or with the use of technological tools. I addressed this limitation through development of an observation platform consisting of a remote controlled video camera suspended from a tethered airship with boat-based monitoring, adjustment, and recording of video. The system was used successfully to conduct continuous behavioral observations of bottlenose dolphins in the Sarasota Bay, FL area. This system allowed me to describe previously unreported foraging behaviors and elucidate functions for behaviors already defined but poorly understood. Dolphin foraging was modeled as a stage-structured sequence of behaviors, with the goal-directed feeding event occurring at the end of a series of search, encounter, and pursuit behaviors. The behaviors preceding a feeding event do not occur in a deterministic sequence, but are adaptive and plastic. A single-step transition analysis beginning with prey capture and receding in time has identified significant links between observed behaviors and demonstrated the stage-structured nature of dolphin foraging. Factors affecting the occurrence of specific behaviors and behavioral transitions include mesoscale habitat variation and individual preferences. The role of sound in foraging, especially echolocation, is less well understood than the behavioral component. Recent studies have explored the use of echolocation in captive odontocete foraging and presumed feeding in wild animals, but simultaneous, detailed behavioral and acoustic observations have eluded researchers. The current study used two methods to obtain acoustic data. The overhead video system includes two towed hydrophones used to record 'ambient' sounds of dolphin foraging. The recordings are of the 'ambient' sounds because the source of the sounds, i.e. animal, could not be localized. Many focal follows, however, were conducted with single animals, and from these records the timing of echolocation and other sounds relative to the foraging sequence could be examined. The 'ambient' recordings revealed that single animals are much more vocal than animals in groups, both overall and during foraging. When not foraging, single animals vocalized at a rate similar to the per animal rate in groups of>=2 animals. For single foraging animals, the use of different sound types varies significantly by the habitat in which the animal is foraging. These patterns of use coupled with the characteristics of the different sound types suggest specific functions for each. The presence of multiple animals in a foraging group apparently reduces the need to vocalize, and potential reasons for this pattern are discussed. In addition, the increased vocal activity of single foraging animals lends support to specific hypotheses of sound use in bottlenose dolphins and odontocetes in general. The second acoustic data collection method records sounds known to be from a specific animal. An acoustic recording tag was developed that records all sounds produced by an animal including every echolocation click. The tag also includes an acoustic sampling interval controller and a sensor suite that measures pitch, roll, heading, and surfacing events. While no foraging events occurred while an animal was wearing an acoustic data logger, the rates of echolocation and whistling during different activities, e.g. traveling, were measured.
by Douglas Paul Nowacek.
Ph.D.

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Ersado, Lire. "Three Essays in Development Economics: Savings Behavior and Risk; Health and Public Investments; and Sequential Technology Adoption." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/28678.

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This dissertation explores household risk and savings behavior in Zimbabwe, and agricultural technology adoption, and the impact of public investments on the economy and community health in Ethiopia. The first paper analyzes changes in per capita consumption and savings behavior in Zimbabwe before and after a range of financial and weather-related shocks using comparable national income, consumption and expenditure surveys of 1990/91 and 1995/96. The empirical results show that before droughts and macroeconomic adjustments Zimbabweans used savings to smooth consumption. In contrast, risk management strategies were severely limited after the shocks; consumption tracked income more closely in the latter period. The inability to effectively address the risks arising from droughts and economy-wide structural changes implies that any subsequent economic and social uncertainty will have serious welfare consequences. The second paper examines the interaction between public investments, community health, and productivity- and land-enhancing technology adoption decisions by farm households in Northern Ethiopia. It models technology adoption as a sequential process where the timing of choices can matter. The econometric test results indicate that the decision and intensity of technology adoption are highly correlated with the sequential nature of adoption. The most striking results concern the importance of disease - the amount of time spent sick and time spent caring for sick family members are inversely associated with both the decision and intensity of technology adoption. Finally the third paper looks at the welfare impacts of a public water resource development project with health side effects in Tigray, Northern Ethiopia. It uses a model of a social planner to characterize the optimal implementation of such projects over time, showing how health and production are important considerations in this decision. The empirical analysis shows that the marginal net benefits of Tigray's current microdam investments are positive. The lost income households suffer from increased time away from productive activities (due to sickness) is compensated for by increased yields and market opportunities brought about through irrigated agriculture. However, it should be noted that this conclusion is based on efficiency and not equity.
Ph. D.

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Chen, Lihui. "Modelling continuous sequential behaviour to enhance training and generalization in neural networks." Thesis, University of St Andrews, 1993. http://hdl.handle.net/10023/13485.

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This thesis is a conceptual and empirical approach to embody modelling of continuous sequential behaviour in neural learning. The aim is to enhance the feasibility of training and capacity for generalisation. By examining the sequential aspects of the passing of time in a neural network, it is suggested that an alteration to the usual goal weight condition may be made to model these aspects. The notion of a goal weight path is introduced, with a path-based backpropagation (PBP) framework being proposed. Two models using PBP have been investigated in the thesis. One is called Feedforward Continuous BackPropagation (FCBP) which is a generalization of conventional BackPropagation; the other is called Recurrent Continuous BackPropagation (RCBP) which provides a neural dynamic system for I/O associations. Both models make use of the continuity underlying analogue-binary associations and analogue-analogue associations within a fixed neural network topology. A graphical simulator cbptool for Sun workstations has been designed and implemented for supporting the research. The capabilities of FCBP and RCBP have been explored through experiments. The results for FCBP and RCBP confirm the modelling theory. The fundamental alteration made on conventional backpropagation brings substantial improvement in training and generalization to enhance the power of backpropagation.

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Goulding, Kevin Norman. "Bidding behavior in sequential auctions for wholesale electricity: a case study of the NYISO." Thesis, Montana State University, 2012. http://etd.lib.montana.edu/etd/2012/goulding/GouldingK0512.pdf.

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This paper investigates the process by which bidders in the NYISO (New York Independent System Operator) market update their bids between the Day-ahead and Hour-ahead markets. Observed bids for the ten largest bidders over the years 2002- 2010 are used to investigate the extent to which observed bids into both the Day-ahead (DA) and Hour-ahead (HA) markets are consistent with joint profit maximization in the two markets. Theory about single period bidding behavior developed in the California spot electricity market (Wolak, 2003) and Texas electricity balancing market (Hortacsu and Puller, 2008) is extended to the two-period case specific to the NYISO market. While uncertainty comes from both the behavior of competing firms and additive uncertainty in demand, bidder behavior is broadly consistent with expected profit maximization against a stochastic piece of demand that is additively separable.

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Cortez, Kristi Cathleen. "A Sequential Analysis of Therapist and Child Social Behavior Following a Conditioned Reinforcement Procedure." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc849669/.

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We conducted a contingency analysis to evaluate if a sequential relation between social initiations and positive social responses increased for both therapists and children with autism following a conditioned reinforcement procedure. Participants included child-therapist dyads, which were previously identified as having low rapport. These dyads were observed prior to and following an intervention designed to establish therapists' social behavior as a reinforcer. Sessions consisted of unstructured play between the therapist and child. Results from a Yule's Q analysis show that both the child and adult positive responding to the others' social initiations increased following the intervention. Findings highlight the reciprocal effects of therapist-child interactions as well as the effectiveness of establishing social attention as a reinforcer via an operant discrimination training procedure.

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Nebout, Antoine. "Decision making under compound uncertainty : experimental study of ambiguity attitudes and sequential choice behavior." Thesis, Montpellier 1, 2011. http://www.theses.fr/2011MON10051.

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Cette thèse appartient au domaine de la théorie de la décision en situation d'incertitude. Elle vise à comprendre, décrire, et représenter les choix individuels dans différents contextes de décision. Notre travail se concentre sur le fait que le comportement économique est souvent influencé par la structure et le déroulement de la résolution de l'incertitude. Dans une première expérience nous avons confronté nos sujets à différents types d'incertitude – à savoir du risque (probabilités connues), de l'incertain (probabilités inconnues), du risque composé et de l'incertain composé – en utilisant des mécanismes aléatoires particuliers. Le chapitre 1 analyse l'hétérogénéité des attitudes individuelles face à l'ambiguïté, au risque composé et à l'incertain composé alors que dans le chapitre 2, le modèle d'espérance d'utilité à dépendance du rang est utilisé comme outil de mesure afin d'étudier en détails ces attitudes au niveau individuel. Le chapitre 3 confronte à l'expérience l'interprétation de l'ambiguïté en terme de croyances de second ordre et propose une méthode d'élicitation de la fonction qui caractérise l'attitude face à l'ambiguïté dans les modèles « récursifs » de décision face à l'incertain. La seconde partie de la thèse s'intéresse aux comportements de décision individuelle dans un contexte dynamique et est composée de deux études expérimentales indépendantes. Néanmoins, elles reposent toutes deux sur la décomposition de l'axiome d'indépendance en trois axiomes dynamiques: conséquentialisme, cohérence dynamique et réduction des loteries composées. Le chapitre 4 rapporte les résultats d'une expérience de décision individuelle sur les facteurs de violations de chacun de ces axiomes. Le chapitre 5 présente une catégorisation conceptuelle des comportements individuels dans des problèmes de décision séquentiels face au risque. Le cas des agents ne se conformant pas à l'axiome d'indépendance y est étudié de façon systématique et les résultats d'une expérience spécialement conçue pour tester cette catégorisation sont présentés
This thesis belongs to the domain of decision theory under uncertainty and aims to understand, describe and represent individual choices in various decision contexts. Our work focuses on the fact that economic behavior is often influenced by the structure and the timing of resolution of uncertainty. In a first experimental part, we confronted subjects with different types of uncertainty, namely risk (known probabilities), uncertainty (unknown probabilities), compound risk and compound uncertainty, which were generated using special random devices. In chapter 1 we analyze the heterogeneity of attitudes towards ambiguity, compound risk and compound uncertainty whereas in chapter 2, we use rank dependent expected utility as a measuring tool in order to individually investigate these attitudes. Chapter 3 confronts the interpretation of ambiguity in term of second order beliefs with the experimental data and proposes a method for eliciting the function that encapsulates attitudes toward ambiguity in the “recursive” or multistage models of decision under uncertainty. The second part of the thesis deals with individual decision making under risk in a dynamic context and is composed of two independent experimental studies. Both of them rely on the decomposition of the independence axiom into three dynamic axioms: consequentialism, dynamic consistency and reduction of compound lotteries. Chapter 4 reports experimental data about violations of each of the three axioms. Chapter 5 presents a conceptual categorization of individual behavior in sequential decision problems under risk, especially those which do not conform to the independence axiom. We propose an experiment specially designed to test the predictions of this categorization

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Lewkowicz, Daniel. "Behavioral and cognitive basis of sequential actions : can human intentions be revealed trough movement kinematics ?" Thesis, Lille 3, 2013. http://www.theses.fr/2013LIL30038/document.

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L'objectif de ma thèse est de participer à la construction d'un nouveau robot humanoïde qui peut réaliser des interactions intuitives avec l'humain à travers l'observation et l'imitation. Pour cela, j'ai conduit une série d'études expérimentales chez le jeune adulte pour caractériser les propriétés cinématiques des mouvements du bras réalisés pendant des interactions motrices et sociales, autant d'éléments qui seront les patterns de référence pour le futur robot. En se concentrant sur le comportement non-verbal, nous avons testé comment les contraintes externes et internes (difficulté, prédictibilité, temporalité) façonne la cinématique des mouvements du bras et de la main dans une simple action séquentielle de prise et de pose d'un objet (étude 1 et 2). Les résultats révèlent des modulations précoces dans la cinématique de la phase d'atteinte et de saisie, en fonction de la taille et de la stabilité du réceptacle terminal sur lequel l'objet devait être placé. Ces modulations observées dans le premier élément de la séquence sont en contradiction avec les modèles d'optimisation de trajectoire utilisés en robotique pour les séquences d'action. Ils suggèrent un couplage fort entre les paramètres moteurs dans une stratégie de planification encapsulée qui rétro-propage les contraintes contextuelles sur les éléments précoces de la séquence. Pour confirmer ces résultats, une seconde série d'étude a été conduite en utilisant des tâches cinématiques et vidéos pour montrer que les intentions motrices humaines pouvaient être lues à travers la détection de ces modulations cinématiques précoces. En utilisant un système de classification artificiel, nous avons testé si les indices de bas niveau pouvaient permettre une catégorisation des essais. Les résultats montrent qu'en absence de capacité cognitive particulière, le réseau de neurone pouvait catégoriser les intentions significativement au-dessus du niveau de la chance en observant les 500 premières millisecondes de l'action (étude 3). La troisième partie de mon travail de thèse s'est tournée vers les mesures en eye-tracking. Nous avons révélé ici que la stratégie proactive de fixations oculaires utilisée pendant l'observation de l'action était similaire à celle utilisée pendant son exécution (étude 4). De plus, les catégorisations correctes d'intentions motrices étaient caractérisées par des saccades plus précises et des fixations plus longues sur l'objet. Les mouvements oculaires sont connus pour jouer un rôle important dans les interactions sociales. Ainsi, dans une dernière expérience (étude 5), nous avons mis en place un jeu compétitif en face à face révélant des effets spécifiques du contexte social qui modifie la cinématique des mouvements d'atteinte selon le type de situations interactives. Dans le manuscrit de thèse je propose une discussion qui replace les résultats dans les modèles neuronaux et cognitifs de l'intégration sensori-mmotrice. Lorsque c'est le cas, des directions futures sont suggérées à la fois pour les modèles cognitifs de contrôle moteur et pour le développement e systèmes artificiels neuro-inspirés intégrant des capacités d'interaction sociale intuitive
The aim of my PhD thesis was to participate in the construction of a new humanoid robot that can sustain intuitive interactions with humans through observation and imitation. As such, I conducted a series of experimental studies in young adults to better characterize the kinematic properties of those arm movements performed during motor and social interactions, elements that are the reference patterns for the to-come robot. Focusing on non-verbal behavior, we tested how external and internal constraints (difficulty, predictability, timing) shaped the kinematics of both arm and hand movements in a very simple pick and place sequential action (study 1 and 2). The results revealed early modulations in kinematics in the reach-to-grasp phase depending of the size and the stability of the target pad on which the object had to be placed. These modulations observed within the first element of the sequence were in contradiction with the current optimized trajectory models used in robotics for action sequences. They suggest in fact a strong coupling of the motor parameters within an encapsulated planning strategy that back-propagates the contextual constraints on to the early elements of the motor sequence. To confirm these findings, a second serie of studies were conducted using kinematic and video based tasks to show that human motor intentions can be read through the detection of these early kinematic modulations (study 3). Using basic artificial classification, we tested whether low-revel motor indices could afford trial categorization without the need for higher-level process such as motor imagery. results indicated that indeed without cognitive abilities the neural network could categorize the intention of an observed action within the first 500ms, significantly above chance level (study 4). The third place of my PhD work turned to eye tracking. Here, we revealed that the proactive strategy of eye-fixations used during action observation were similar to those made during executed actions. Additionally, good categorization of motor intention was characterized by more accurate saccades and longer object fixations. Eye movements are known to play an important role in social intercations. Hence, in a final experiment (study 5), we setup a face-to-face competitive game to reveal the specific effects thet the social context may play on the kinematic properties of reaching during different types of interactive situations. In the PhD mansucript, I propose a general discussion that sets these results within the current cognitive and neuronal models of sensori-motor integration. When appropriate, future directions are suggested both for cognitive models of motor control and for the development of neuro-inspired articicial systems constitued with intuitive social interaction skills

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Hall, Kara L. "A meta-analytic examination of decisional balance across stage transitions : a cross-sectional analysis and cross-sequential cross-validation /." View online ; access limited to URI, 2004. http://0-wwwlib.umi.com.helin.uri.edu/dissertations/dlnow/3145423.

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Seo, M. "The role of front-striatal brain circuits and dopamine in cognitive motor control of sequential behaviour." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1420697/.

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Our daily lives are filled with routine behaviours that we develop with repeated practice over time. These routine behaviours, often executed automatically without requiring much attention become an integral part of our lives. However, a seemingly effective automatic behaviour can become inappropriate or inefficient with changes in the environment and we naturally turn to a more adaptable, perceptually guided behaviour to achieve the same goal. What are the networks that mediate these automatic and perceptually guided behaviours? This thesis focuses on understanding the role of frontal-striatal circuits in the cognitive motor control of sequential behaviour, as well as the contribution of dopamine (DA) in these areas. The aim of the studies presented in this work was to address these questions from a number of perspectives. Firstly, in an awake-behaving non-human primate study the goal was to develop a behavioural task that differentiates the automatic and attention demanding sequential actions. Secondly, ensembles of neurons in the frontal cortex and the dorsal striatum were recorded simultaneously with a multichannel single unit recording system to characterise neural responses to our different task conditions and thereby investigating the role of prefrontal cortex and the dorsal striatum in these behaviours. Thirdly, we locally injected DA receptor antagonists into the dorsal striatum, during the behavioural task to examine the effects of DA on behaviour. Finally, in a study using patients with Parkinson’s disease we examined their performance in a sequence learning task from positive and negative feedback processing while they were off and on their DA medication. This approach helped to strengthen the link between findings in the non-human primate and the human subjects with specific involvement of DA or disruption of the frontal-striatal circuits in sequence learning.

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Cheng, Heng-Tze. "Learning and Recognizing The Hierarchical and Sequential Structure of Human Activities." Research Showcase @ CMU, 2013. http://repository.cmu.edu/dissertations/293.

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The mission of the research presented in this thesis is to give computers the power to sense and react to human activities. Without the ability to sense the surroundings and understand what humans are doing, computers will not be able to provide active, timely, appropriate, and considerate services to the humans. To accomplish this mission, the work stands on the shoulders of two giants: Machine learning and ubiquitous computing. Because of the ubiquity of sensor-enabled mobile and wearable devices, there has been an emerging opportunity to sense, learn, and infer human activities from the sensor data by leveraging state-of-the-art machine learning algorithms. While having shown promising results in human activity recognition, most existing approaches using supervised or semi-supervised learning have two fundamental problems. Firstly, most existing approaches require a large set of labeled sensor data for every target class, which requires a costly effort from human annotators. Secondly, an unseen new activity cannot be recognized if no training samples of that activity are available in the dataset. In light of these problems, a new approach in this area is proposed in our research. This thesis presents our novel approach to address the problem of human activity recognition when few or no training samples of the target activities are available. The main hypothesis is that the problem can be solved by the proposed NuActiv activity recognition framework, which consists of modeling the hierarchical and sequential structure of human activities, as well as bringing humans in the loop of model training. By injecting human knowledge about the hierarchical nature of human activities, a semantic attribute representation and a two-layer attribute-based learning approach are designed. To model the sequential structure, a probabilistic graphical model is further proposed to take into account the temporal dependency of activities and attributes. Finally, an active learning algorithm is developed to reinforce the recognition accuracy using minimal user feedback. The hypothesis and approaches presented in this thesis are validated by two case studies and real-world experiments on exercise activities and daily life activities. Experimental results show that the NuActiv framework can effectively recognize unseen new activities even without any training data, with up to 70-80% precision and recall rate. It also outperforms supervised learning with limited labeled data for the new classes. The results significantly advance the state of the art in human activity recognition, and represent a promising step towards bridging the gap between computers and humans.

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Schenk, Merritt J. "Further analysis of delay discounting: Sequential effects on participant answers using the 27-item Monetary Choice Questionnaire." Scholarly Commons, 2016. https://scholarlycommons.pacific.edu/uop_etds/283.

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Systematic manipulations of the order in which questions are presented in hypothetical discounting tasks have shown that individual responses vary as a result of these manipulations. For example, Robles and Vargas (2007, 2008) and Robles, Vargas, and Bejarano (2009) demonstrated that individual discounting rates systematically change if questions are presented in a random, ascending, or descending order. The purpose of this study was to examine if specific sequential manipulations affected individual k values when using the Kirby, Petry, and Bickel (1999) 27-item Monetary Choice Questionnaire (MCQ). In a single session, participants (undergraduate students, N = 80), answered two MCQs. One of the MCQs was the standard Kirby et al. (1999) MCQ and the other was the MCQ with the question sequence altered systematically. Within-subject results suggest that individual k values are consistent when comparing k values from the two MCQs completed by each individual. In most cases, individual k values between MCQs did not vary substantially. Additionally, there was a statistically significant correlation between both MCQ administrations for each group. Results from this study indicate that k values obtained using the MCQ are reliable when question sequence is altered.

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Weng, Zhiquan. "Consumer Search and Firm-Worker Reciprocity: A Behavioral Approach." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1281985969.

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He, Jun. "Evaluating and Reducing the Effects of Misclassification in a Sequential Multiple Assignment Randomized Trial (SMART)." VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5678.

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SMART designs tailor individual treatment by re-randomizing patients to subsequent therapies based on their response to initial treatment. However, the classification of patients being responders/non-responders could be inaccurate and thus lead to inappropriate treatment assignment. In a two-step SMART design, by assuming equal randomization, and equal variances of misclassified patients and correctly classified patients, we evaluated misclassification effects on mean, variance, and type I error/ power of single sequential treatment outcome (SST), dynamic treatment outcome (DTRs), and overall outcome. The results showed that misclassification could introduce bias to estimates of treatment effect in all types of outcome. Though the magnitude of bias could vary according to different templates, there were a few constant conclusions: 1) for any fixed sensitivity the bias of mean of SSTs responders always approached to 0 as specificity increased to 1, and for any fixed specificity the bias of mean of SSTs non-responders always approached to 0 as sensitivity increased to 1; 2) for any fixed specificity there was monotonic nonlinear relationship between the bias of mean of SSTs responders and sensitivity, and for any fixed sensitivity there was also monotonic nonlinear relationship between the bias of mean of SSTs non-responders and specificity; 3) the bias of variance of SSTs was always non-monotone nonlinear equation; 4) the variance of SSTs under misclassification was always over-estimated; 5) the maximized absolute relative bias of variance of SSTs was always ¼ of the squared mean difference between misclassified patients and correctly classified patients divided by true variance, but it might not be observed in the range of sensitivity and specificity (0,1); 6) regarding to sensitivity and specificity, the bias of mean of DTRs or overall outcomes was always linear equation and their bias of variance was always non-monotone nonlinear equation; 7) the relative bias of mean/ variance of DTRs or overall outcomes could approach to 0 where sensitivity or specificity wasn’t necessarily to be 1. Furthermore, the results showed that the misclassification could affect statistical inference. Power could be less or bigger than planned 80% under misclassification and showed either monotonic or non-monotonic pattern as sensitivity or specificity decreased. To mitigate these adverse effects, patient observations could be weighted by the likelihood that their response was correctly classified. We investigated both normal-mixture-model (NM) and k-nearest-neighbor (KNN) strategies to attempt to reduce bias of mean and variance and improve inference at final stage outcome. The NM estimated the early stage probabilities of being a responder for each patient through optimizing the likelihood function by EM algorithm, while KNN estimated these probabilities based upon classifications for the k nearest observations. Simulations were used to compare the performance of these approaches. The results showed that 1) KNN and NM produced modest reductions of bias of point estimates of SSTs; 2) both strategies reduced bias on point estimates of DTRs when the misclassified patients and correctly classified patients from same initial treatment had unequal means; 3) NM reduced the bias of point estimates of overall outcome more than KNN; 4) in general, there were little effect on power adjustment; 5) type I error should always be preserved at 0.05 regardless of misclassification when same response rate and same treatment effects among responders or among non-responders were assumed, but the observed type I error tended to be less than 0.05; 6) KNN preserved type I error at 0.05, but NM might increase type I error rate. Even though most of time both KNN and NM strategies improved point estimates in SMART designs while we knew misclassification might be involved, the tradeoff were increased type I error rate and little effect on power. Our work showed that misclassification should be considered in SMART design because it introduced bias, but KNN or NM strategies at the final stage couldn’t completely reduce bias of point estimates or improve power. However, in future by adjusting with covariates, these two strategies might be used to improve the classification accuracy in the early stage outcomes.

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Rampal, Jeevant. "Behavioral Economic Theory and Experimental Investigation." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1491972688590258.

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Vallozzi, Angelo. "Shear behavior of reinforced concrete slabs under concentrated load: an investigation through Sequentially Linear Analysis." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/3238/.

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ABSTRACT (italiano) Con crescente attenzione riguardo al problema della sicurezza di ponti e viadotti esistenti nei Paesi Bassi, lo scopo della presente tesi è quello di studiare, mediante la modellazione con Elementi Finiti ed il continuo confronto con risultati sperimentali, la risposta in esercizio di elementi che compongono infrastrutture del genere, ovvero lastre in calcestruzzo armato sollecitate da carichi concentrati. Tali elementi sono caratterizzati da un comportamento ed una crisi per taglio, la cui modellazione è, da un punto di vista computazionale, una sfida piuttosto ardua, a causa del loro comportamento fragile combinato a vari effetti tridimensionali. La tesi è incentrata sull'utilizzo della Sequentially Linear Analysis (SLA), un metodo di soluzione agli Elementi Finiti alternativo rispetto ai classici approcci incrementali e iterativi. Il vantaggio della SLA è quello di evitare i ben noti problemi di convergenza tipici delle analisi non lineari, specificando direttamente l'incremento di danno sull'elemento finito, attraverso la riduzione di rigidezze e resistenze nel particolare elemento finito, invece dell'incremento di carico o di spostamento. Il confronto tra i risultati di due prove di laboratorio su lastre in calcestruzzo armato e quelli della SLA ha dimostrato in entrambi i casi la robustezza del metodo, in termini di accuratezza dei diagrammi carico-spostamento, di distribuzione di tensioni e deformazioni e di rappresentazione del quadro fessurativo e dei meccanismi di crisi per taglio. Diverse variazioni dei più importanti parametri del modello sono state eseguite, evidenziando la forte incidenza sulle soluzioni dell'energia di frattura e del modello scelto per la riduzione del modulo elastico trasversale. Infine è stato effettuato un paragone tra la SLA ed il metodo non lineare di Newton-Raphson, il quale mostra la maggiore affidabilità della SLA nella valutazione di carichi e spostamenti ultimi insieme ad una significativa riduzione dei tempi computazionali. ABSTRACT (english) With increasing attention to the assessment of safety in existing dutch bridges and viaducts, the aim of the present thesis is to study, through the Finite Element modeling method and the continuous comparison with experimental results, the real response of elements that compose these infrastructures, i.e. reinforced concrete slabs subjected to concentrated loads. These elements are characterized by shear behavior and crisis, whose modeling is, from a computational point of view, a hard challenge, due to their brittle behavior combined with various 3D effects. The thesis is focused on the use of Sequentially Linear Analysis (SLA), an alternative solution technique to classical non linear Finite Element analyses that are based on incremental and iterative approaches. The advantage of SLA is to avoid the well-known convergence problems of non linear analyses by directly specifying a damage increment, in terms of a reduction of stiffness and strength in the particular finite element, instead of a load or displacement increment. The comparison between the results of two laboratory tests on reinforced concrete slabs and those obtained by SLA has shown in both the cases the robustness of the method, in terms of accuracy of load-displacements diagrams, of the distribution of stress and strain and of the representation of the cracking pattern and of the shear failure mechanisms. Different variations of the most important parameters have been performed, pointing out the strong incidence on the solutions of the fracture energy and of the chosen shear retention model. At last a confrontation between SLA and the non linear Newton-Raphson method has been executed, showing the better reliability of the SLA in the evaluation of the ultimate loads and displacements, together with a significant reduction of computational times.

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Ecker, Andrew Joseph. "Initial Principal Readiness to Interconnect Positive Behavioral Interventions and Supports and School Mental Health| A Sequential Multivariate Exploratory Analysis." Thesis, Manhattanville College, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10621987.

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Approximately 20% of youth in the U.S. are experiencing a mental health challenge; a rate that is said to increase by more than 50% by 2020. Schools are the largest provider of mental health services to youth, yet two of schools’ most efficacious evidence-based systems, Positive Behavioral Interventions and Supports (PBIS) and school mental health (SMH), often exist in isolation. Interconnected Systems Framework (ISF) unites these two systems to improve school and life outcomes for all students, but especially, students who struggle with or are at risk of developing mental health challenges. The current study measured New York City metropolitan area principals’ initial readiness to implement ISF. This researcher found that principals in schools that implemented PBIS indicated significantly greater levels of initial readiness to implement ISF than principals in schools that did not implement PBIS. Sequential multiple regression models showed the variance of independent variables, elements of ISF, that predicted initial readiness to implement ISF. The elements “teaching appropriate behaviors to all students” and “acknowledging all students for behavioral achievement, school-wide”, serve as strong recommendations for principals in the exploration and adoption stage of ISF. As policy makers prepare for the new presidency and the inception of the Every Student Succeeds Act (ESSA), they should reflect on the goals, strengths, and needs of their students and equip students, families, schools, and communities so they can be achieved. Although most of data analysis yields to no significance, that in and of itself is significant. Student need and implementation challenges are consistent across the region.

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Monteiro, Pedro Tiago dos Santos. "Experimental studies in simple choice behaviour." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:ae36e6ba-c4ff-4b5f-9f49-5c921707baa2.

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This thesis addresses decision mechanisms in foraging situations, using laboratory experiments with European starlings (Sturnus vulgaris). Building on previous work from the Behavioural Ecology Research Group, I chose the Sequential Choice Model (SCM; reviewed in Kacelnik et al., 2011 − Appendix 1) as a starting point, and tested its premises and predictions generalising it to different experimental protocols. Classical decision models do not relate choice preferences to behaviour towards isolated options, and assume that choices involve time-consuming evaluations of all alternatives. However, previous work found that starlings’ responses to isolated options predict preference in choices, and that response times to single-option encounters are not reliably longer than response times in choices. Since, in the wild, options are normally encountered sequentially, dealing with isolated options can be considered of greater biological, and possibly psychological, significance than simultaneous decisions. Following this rationale, the SCM postulates that when multiple simultaneous stimuli are met they are processed in parallel, each competing against the memory of background opportunities, rather than comparing present options to each other. At the time of launching this research, these ideas had only been applied to protocols involving just two deterministic alternatives and offering no chance to explore the influence of learning history (i.e., how animals learn to choose; see Chapter 4). To increase their relevance and offer more rigorous tests, I generalised them to situations with multiple (see Chapters 2, 4 and 5), and in some cases probabilistic alternatives (see Chapter 3), controlling the learning regime. I combined these extensions with tests of economic rationality (see Chapter 6), a concept that is presently facing sustained debates. Integrating the result of all experimental chapters (see Chapter 7), my results support the notion that behaviour in single-option encounters is fundamental to understand choice behaviour. The important issue of whether choices involve a decision time cost or the opposite, a shortening of response times, remains unsolved, as neither could be evidenced reliably.

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Tidd, Brendan. "Learning visuo-motor behaviours for robot locomotion over difficult terrain." Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/235891/1/Brendan%2BTidd%2BThesis%281%29.pdf.

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This thesis investigated efficient methods for learning locomotion behaviours for robots, and the challenges of combining several complex controllers. Experiments were performed with a dynamic biped in simulation required to walk across gaps, over steps and stairs, and jump over hurdles and blocks, and also in a real-world scenario with a large tracked platform negotiating small doorways. The developed solutions utilised perception to perform complex maneuvers while minimising retraining for new behaviours. Ideas from this thesis lead toward scalable behaviour libraries to enable robots to make their way into an increasing number of roles in our society.

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Pamplin, Jason Andrew. "Formal Object Interaction Language: Modeling and Verification of Sequential and Concurrent Object-Oriented Software." unrestricted, 2007. http://etd.gsu.edu/theses/available/etd-04222007-205349/.

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Thesis (Ph. D.)--Georgia State University, 2007.
Title from file title page. Ying Zhu, committee chair; Xiaolin Hu, Geoffrey Hubona, Roy Johnson, Rajshekhar Sunderraman, committee members. Electronic text (216 p. : ill. (some col.)) : digital, PDF file. Description based on contents viewed Nov. 29, 2007. Includes bibliographical references (p. 209-216).

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Descamps, Ambroise David Damian. "Essays on information and beliefs in dynamic choices." Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/121077/1/Ambroise%20David%20Damian_Descamps_Thesis.pdf.

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This thesis investigates how information is processed and used for economic decision making. It is composed of four essays that use theory, experiments and econometrics to investigate dynamic behaviour. The first part of my thesis studies how costly information is gathered and used in a risky environment. I explore how behavioural biases affect information processing and decisions. The second part of my thesis studies how relative performance feedback affects behaviour in competitions. Using new econometric methods and a novel experimental design, I provide evidence in favour of a "positive momentum", whereby past performance has a positive impact on later performance.

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Žakelj, Blaž. "Experimental Investigations on Market Behavior." Doctoral thesis, Universitat Pompeu Fabra, 2012. http://hdl.handle.net/10803/80908.

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This thesis is a collection of three essays on inflation expectations, forecasting uncertainty, and the role of uncertainty in sequential auctions, all using experimental approach. Chapter 1 studies how individuals forecast inflation in fictitious macroeconomic setup and analyzes the effect of monetary policy rules on their decisions. Results display heterogeneity in inflation forecasting rules and demonstrate the importance of adaptive learning forecasting if model switching is assumed. Chapter 2 extends the analysis from Chapter 1 by analyzing individual inflation forecasting uncertainty. Results show that confidence intervals depend on inflation variance and business cycle phase, have a strong inertia, and are often asymmetric. Finally, Chapter 3 analyzes the role of uncertainty about the number of bidders for the behavior of subjects in a sequential auction experiment. Uncertainty does not aggravate price decline, but it changes individual bidding strategies and auction efficiency.
Esta tesis consta de tres ensayos sobre las expectativas de inflación, la incertidumbre de la predicción, y la importancia de la incertidumbre en subastas secuenciales. Todos ellos utilizan un método experimental. El capítulo 1 estudia cómo los individuos predicen la inflación en la economía ficticia y analiza el efecto de las reglas de política monetaria en sus decisiones. Los resultados revelan la heterogeneidad en las reglas de predicción de la inflación y demuestran la importancia del mecanismo de aprendizaje adaptivo si el cambio entre los modelos se supone. Capítulo 2 continúa el análisis del capítulo 1, analiza la incertidumbre individual de las expectativas de inflación. Los resultados muestran que los intervalos de confianza dependen de varianza de la inflación y la fase del ciclo económico, tienen una fuerte inercia, y son frecuentemente asimétricos. Por último, el capítulo 3 analiza la influencia de la incertidumbre sobre el número de oferentes en el comportamiento de los individuos en un experimento de la subasta secuencial. La incertidumbre no agrava la caída de los precios, pero cambia las estrategias de los oferentes y la eficiencia de la subasta.

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Pieraccini, Luca. "Shear behaviour of reinforced cconcrete slab under concentrated load: an investigation through non-linear and sequentially linear analysis." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amslaurea.unibo.it/5902/.

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English: The assessment of safety in existing bridges and viaducts led the Ministry of Public Works of the Netherlands to finance a specific campaing aimed at the study of the response of the elements of these infrastructures. Therefore, this activity is focused on the investigation of the behaviour of reinforced concrete slabs under concentrated loads, adopting finite element modeling and comparison with experimental results. These elements are characterized by shear behaviour and crisi, whose modeling is, from a computational point of view, a hard challeng, due to the brittle behavior combined with three-dimensional effects. The numerical modeling of the failure is studied through Sequentially Linear Analysis (SLA), an alternative Finite Element method, with respect to traditional incremental and iterative approaches. The comparison between the two different numerical techniques represents one of the first works and comparisons in a three-dimensional environment. It's carried out adopting one of the experimental test executed on reinforced concrete slabs as well. The advantage of the SLA is to avoid the well known problems of convergence of typical non-linear analysis, by directly specifying a damage increment, in terms of reduction of stiffness and resistance in particular finite element, instead of load or displacement increasing on the whole structure . For the first time, particular attention has been paid to specific aspects of the slabs, like an accurate constraints modeling and sensitivity of the solution with respect to the mesh density. This detailed analysis with respect to the main parameters proofed a strong influence of the tensile fracture energy, mesh density and chosen model on the solution in terms of force-displacement diagram, distribution of the crack patterns and shear failure mode. The SLA showed a great potential, but it requires a further developments for what regards two aspects of modeling: load conditions (constant and proportional loads) and softening behaviour of brittle materials (like concrete) in the three-dimensional field, in order to widen its horizons in these new contexts of study.

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35

Moran, Wayne Gordon. "Information Technology Sourcing Across Cultures: Preparing Leaders for Cross-Cultural Engagements and Implementing Best Practices with Cultural Sensitivity." Antioch University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1411641924.

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36

Mantovani, Marco. "Essays in forward looking behavior in strategic interactions." Doctoral thesis, Universite Libre de Bruxelles, 2013. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209492.

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The general topic of our thesis is forward looking behavior in strategic situations. Mixing theoretical and experimental analysis, we document how strategic thinking is affected by the specific features of a dynamic interaction. The overarching result is that the information regarding decisions that are close to the current one, receive a qualitatively different consideration, with respect to distant ones. That is, the actual decisions are based on reasoning over a limited number of steps, close to actual decison node. We capture this feature of behavior both in a strategic (limited backward induction) and in a non-strategic (limited farsightedness) set up, and we identify relevant consequences on the outcome of the interaction, which powerfullly explain many observed experimental regularities.

In the first essay, we present a general out-of-equilibrium framework for strategic thinking in sequential games. It assumes the agents to take decisions on restricted game trees, according to their (limited) foresight level, following backward induction. Therefore we talk of limited backward induction (LBI). We test for LBI using a variant of the race game. Our design allows to identify restricted game trees and backward reasoning, thus properly disentangling LBI behavior. The results provide strong support in favor of LBI. Most players solve intermediate tasks - i.e. restricted games - without reasoning on the terminal histories. Only a small fraction of subjects play close to equilibrium, and (slow) convergence toward it appears, though only in the base game. An intermediate task keeps the subjects off the equilibrium path longer than in the base game. The results cannot be rationalized using the most popular models of strategic reasoning, let alone equilibrium analysis.

In the second essay, a subtle implication of the model is investigated: the sensitivity of the players’ foresight to the accessibility and completeness of the information they have, using a Centipede game. By manipulating the way in which information is provided to subjects, we show that reduced availability of information is sufficient to shift the distribution of take-nodes further from the equilibrium prediction. On the other hand, similar results are obtained in a treatment where reduced availability of information is combined with an attempt to elicit preferences for reciprocity, through the presentation of the centipede as a repeated trust game. Our results could be interpreted as cognitive limitations being more effective than preferences in determining (shifts in) behavior in our experimental centipede. Furthermore our results are at odds with the recent ones in Cox [2012], suggesting caution in generalizing their results. Reducing the availability of information may hamper backward induction or induce myopic behavior, depending on the strategic environment.

The third essay consists of an experimental investigation of farsighted versus myopic behavior in network formation. Pairwise stability Jackson and Wolinsky [1996] is the standard stability concept in network formation. It assumes myopic behavior of the agents in the sense that they do not forecast how others might react to their actions. Assuming that agents are perfectly farsighted, related stability concepts have been proposed. We design a simple network formation experiment to test these extreme theories, but find evidence against both of them: the subjects are consistent with an intermediate rule of behavior, which we interpret as a form of limited farsightedness. On aggregate, the selection among multiple pairwise stable networks (and the performance of farsighted stability) crucially depends on the level of farsightedness needed to sustain them, and not on efficiency or cooperative considerations. Individual behavior analysis corroborates this interpretation, and suggests, in general, a low level of farsightedness (around two steps) on the part of the agents.
Doctorat en Sciences économiques et de gestion
info:eu-repo/semantics/nonPublished

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Englund, Göran. "Competition in caddis larvae." Doctoral thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 1992. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-101356.

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This thesis deals with behavioural strategies used by caddis larvae in pairwise contests and when selecting microhabitats. Effects of caddis larvae on survival and habitat selection of other insect taxa have also been studied. The behaviours used by Arctopsyche ladogensis larvae fighting for nets, and Agrypnia pagetana larvae fighting for cases, agreed well with predictions from the sequential assessment game, which is an ESS model of animal fighting behaviour. Establishment by net-spinning Hydropsyche siltalai larvae on artificial substrates was highest at intermediate densities of residents. Emigration/mortality was density independent, and it was higher at a poor site (low food availability) than at a rich site. Establishment was unaffected by site quality. Growth was density dependent because larvae in upstream positions reduced both current velocity and concentration of food particles for larvae in downstream positions. A field experiment involved manipulations of the density of H. siltalai larvae and their nets in a lake outlet stream. H. siltalai larvae affected all abundant taxa, but the mechanism involved varied between taxa. Rhyacophila nubila (Trichoptera) and chironomid larvae benefited from the presence of H. siltalai nets. Negative effects on nymphs of the mayfly Ephemerella ignita were due to predation by H. siltalai larvae, while a combination of predation and increased emigration in response to nets depressed densities of Simulium truncatum blackfly larvae.

Diss. (sammanfattning) Umeå : Umeå universitet, 1992, härtill 5 uppsatser

digitalisering@umu

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Sha, Long. "Representing and predicting multi-agent data in adversarial team sports." Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/116506/1/Long_Sha_Thesis.pdf.

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This thesis addresses the theoretical challenges of the application of Artificial Intelligence (AI) to the domain of sports. The key contribution of this work is a new data representation that allows AI algorithms to understand real world sports games such as basketball and soccer. The theoretical advances that this thesis has contributed has the potential to make a significant impact on many aspects of sport analytics, such as prediction, retrieval and simulation. Intelligent systems have been developed based upon this method which enables active spectator engagement in sporting events and more effective coaching of athletes.

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Pickens, Laura R. G. "The Effects of Chronic Adolescent Nicotine Exposure on Adult Cognition in the Male and Female Rat." Kent State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=kent1353723298.

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Kecinski, Maik [Verfasser], and Thomas [Akademischer Betreuer] Riechmann. "Competitiveness and spiteful behaviorin simultaneous and sequential oligopoly quantity games : a two period model with the possibility to lower marginal cost after period one / Maik Kecinski. Betreuer: Thomas Riechmann." Kaiserslautern : Technische Universität Kaiserslautern, 2012. http://d-nb.info/1029083746/34.

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41

Perdikis, Dionysios. "Functionnal organization of complex behavioral processes." Thesis, Aix-Marseille 2, 2011. http://www.theses.fr/2011AIX22050/document.

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Selon des études comportementales, les comportements complexes sont des processus multi-échelles, souvent composés de sous-éléments (unités fonctionnelles ou primitives). Cette thèse propose des architectures fonctionnelles afin de représenter la structure dynamique des unités fonctionnelles ainsi que celle des comportements multi-échelles résultants. Dans un premier temps, des unités fonctionnelles sont modélisées comme des flux structurés de faible dimension dans l'espace de phase (modes de fonctionnement). Des dynamiques supplémen-taires (signaux opérationnels) opèrent sur ces modes de fonctionnement faisant émerger des comportements complexes et sont classifiés selon la séparation entre leur échelle temporelle et celle des modes. Ensuite, des mesures de complexité, appliquées sur des architectures dis-tinctes composant un mouvement simple, révèlent un compromis entre la complexité des modes de fonctionnement et celle des signaux opérationnels. Celui-ci dépend de la séparation entre leurs échelles temporelles et soutient l'efficacité des architectures utilisant des modes non triviaux. Dans un deuxième temps, une architecture pour le comportement séquentiel (ici l'écriture) est construite via le couplage des modes de fonctionnement (réalisant des lettres) et des signaux opérationnels, ceux-ci beaucoup plus lents ou beaucoup plus rapides. Ainsi, l'importance des interactions entre les échelles temporelles pour l'organisation du comporte-ment est illustrée. Enfin, les contributions des modes et des signaux sur la sortie de l'architec-ture sont déterminées. Ceci semble être uniquement possible grâce à l'analyse du flux de phase (c'est-à-dire, non pas à partir des trajectoires dans l'espace de phase ni des séries temporelles)
Behavioural studies suggest that complex behaviours are multiscale processes, which may be composed of elementary ones (units or primitives). Traditional approaches to cognitive mod-elling generally employ reductionistic (mostly static) representations and computations of simplistic dynamics. The thesis proposes functional architectures to capture the dynamical structure of both functional units and the composite multiscale behaviours. First, a mathe-matical formalism of functional units as low dimensional, structured flows in phase space is introduced (functional modes). Second, additional dynamics (operational signals), which act upon functional modes for complex behaviours to emerge, are classified according to the separation between their characteristic time scale and the one of modes. Then, complexity measures are applied to distinct architectures for a simple composite movement and reveal a trade off between the complexities of functional modes and operational signals, depending on their time scale separation (in support of the control effectiveness of architectures employing non trivial modes). Subsequently, an architecture for serial behaviour (along the example of handwriting) is demonstrated, comprising of functional modes implementing characters, and operational signals much slower (establishing a mode competition and ‘binding’ modes into sequences) or much faster (as meaningful perturbations). All components being coupled, the importance of time scale interactions for behavioural organization is illustrated. Finally, the contributions of modes and signals to the output are recovered, appearing to be possible only through analysis of the output phase flow (i.e., not from trajectories in phase space or time)

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Intermaggio, Victor G. "Modeling Confidence and Response Time in Brightness Discrimination: Testing Models of the Decision Process with Controlled Variability in Stimulus Strength." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1337642308.

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43

Steau, Edward. "Behaviour of cold-formed light gauge steel frame floor-ceiling systems in fire." Thesis, Queensland University of Technology, 2019. https://eprints.qut.edu.au/135182/1/Edward_Steau_Thesis.pdf.

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This research has advanced the knowledge and understanding of the behaviour of Light gauge Steel Frame (LSF) floor-ceiling systems in fire based on material and component level fire testing and associated numerical modelling. It has shown that LSF floor-ceiling systems made of innovative rectangular hollow flange channel beams and steel sheathing on one or both sides of gypsum plasterboard linings improve their fire resistance. These floor-ceiling systems are suitable for a range of applications in the building industry.

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France, Tami J. "A Mixed Methods Study: Dimensions of Cross-Cultural Professional Success: Experiences of Western Women Living and Working in Eastern Cultures." Antioch University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1443025671.

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45

Almuhisen, Feda. "Leveraging formal concept analysis and pattern mining for moving object trajectory analysis." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0738/document.

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Cette thèse présente un cadre de travail d'analyse de trajectoires contenant une phase de prétraitement et un processus d’extraction de trajectoires d’objets mobiles. Le cadre offre des fonctions visuelles reflétant le comportement d'évolution des motifs de trajectoires. L'originalité de l’approche est d’allier extraction de motifs fréquents, extraction de motifs émergents et analyse formelle de concepts pour analyser les trajectoires. A partir des données de trajectoires, les méthodes proposées détectent et caractérisent les comportements d'évolution des motifs. Trois contributions sont proposées : Une méthode d'analyse des trajectoires, basée sur les concepts formels fréquents, est utilisée pour détecter les différents comportements d’évolution de trajectoires dans le temps. Ces comportements sont “latents”, "emerging", "decreasing", "lost" et "jumping". Ils caractérisent la dynamique de la mobilité par rapport à l'espace urbain et le temps. Les comportements détectés sont visualisés sur des cartes générées automatiquement à différents niveaux spatio-temporels pour affiner l'analyse de la mobilité dans une zone donnée de la ville. Une deuxième méthode basée sur l'extraction de concepts formels séquentiels fréquents a également été proposée pour exploiter la direction des mouvements dans la détection de l'évolution. Enfin, une méthode de prédiction basée sur les chaînes de Markov est présentée pour prévoir le comportement d’évolution dans la future période pour une région. Ces trois méthodes sont évaluées sur ensembles de données réelles . Les résultats expérimentaux obtenus sur ces données valident la pertinence de la proposition et l'utilité des cartes produites
This dissertation presents a trajectory analysis framework, which includes both a preprocessing phase and trajectory mining process. Furthermore, the framework offers visual functions that reflect trajectory patterns evolution behavior. The originality of the mining process is to leverage frequent emergent pattern mining and formal concept analysis for moving objects trajectories. These methods detect and characterize pattern evolution behaviors bound to time in trajectory data. Three contributions are proposed: (1) a method for analyzing trajectories based on frequent formal concepts is used to detect different trajectory patterns evolution over time. These behaviors are "latent", "emerging", "decreasing", "lost" and "jumping". They characterize the dynamics of mobility related to urban spaces and time. The detected behaviors are automatically visualized on generated maps with different spatio-temporal levels to refine the analysis of mobility in a given area of the city, (2) a second trajectory analysis framework that is based on sequential concept lattice extraction is also proposed to exploit the movement direction in the evolution detection process, and (3) prediction method based on Markov chain is presented to predict the evolution behavior in the future period for a region. These three methods are evaluated on two real-world datasets. The obtained experimental results from these data show the relevance of the proposal and the utility of the generated maps

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Akinyemi, Segun Ajayi. "Geochemical and mineralogical evaluation of toxic contaminants mobility in weathered coal fly ash: as a case study, Tutuka dump site, South Africa." Thesis, University of the Western Cape, 2011. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_1226_1360593017.

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The management and disposal of huge volumes of coal combustion by products such as fly ash has constituted a major challenge to the environment. In most cases due to the inadequate alternative use of coal fly ash, the discarded waste is stored in holding ponds, slag heaps, or stock piled in ash dumps. This practice has raised concerns on the prospect of inorganic metals release to the surface and groundwater in the vicinity of the ash dump. Acceptable scientific studies are lacking to determine the best ash disposal practices. Moreover, knowledge about the mobility patterns of inorganic species as a function of mineralogical association or pH susceptibility of the dry disposed ash dump under natural weathering conditions are scarce in the literature. Fundamental understanding of chemical interactions of dry disposed ash with ingressed CO2 from atmosphere, percolating rain water and brine irrigation within ash disposal sites were seen as key areas requiring investigation. The mineralogical association of inorganic species in the dry disposed ash cores can be identified and quantified. This would provide a basis for understanding of chemical weathering, mineralogical transformations or mobility patterns of these inorganic species in the dry ash disposal scenario. The current study therefore aims to provide a comprehensive characterisation of weathered dry disposed ash cores, to reveal mobility patterns of chemical species as a function of depth and age of ash, with a view to assessing the potential environmental impacts. Fifty-nine samples were taken from 3 drilled cores obtained respectively from the 1 year, 8 year and 20-year-old sections of sequentially dumped,
weathered, dry disposed ash in an ash dump site at Tutuka - a South African coal burning power station. The core samples were characterized using standard analytical procedures viz: X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transforms infrared (FTIR) techniques, Scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) and Acid neutralisation capacity (ANC) test. A modified sequential extraction (SE) method was used in this study. The chemical partitioning, mobility and weathering patterns in 1 year, 8 year and 20-year-old sections of the ash dump were respectively investigated using this modified sequential extraction scheme. The sequence of the extractions was as follows: (1) water soluble, (2) exchangeable, (3) carbonate, (4) iron and manganese and (5) residual. The results obtained from the 5 steps sequential extraction scheme were validated with the total metal content of the original sample using mass balance method. The distribution of major and trace elements in the different liquid fractions obtained after each step of sequential extraction of the 59 drilled core samples was determined by inductively coupled plasma mass spectrometry (ICPMS). The data generated for various ash core samples were explored for the systematic analysis of mineralogical transformation and change in ash chemistry with ageing of the ash. Furthermore, the data was analyzed to reveal the impact of ingressed CO2 from atmosphere, infiltrating rain water and brine irrigation on the chemistry of ash core samples. Major mineral phases in original ash core samples prior to extraction are quartz (SiO2) and mullite (3Al2O3·
2SiO2). Other minor mineral phases identified were hematite (Fe2O3), calcite (CaCO3), lime (CaO), anorthite (CaAl2Si2O8), mica (Ca (Mg, Al)3 (Al3Si) O10 (OH)2), and enstatite (Mg2Si2O6). X-ray diffraction results show significant loss of crystallinity in the older ash cores. The presence of minor phases of calcite and mica in dry disposed ash cores are attributed to reduction in the pore water pH due to hydration, carbonation and pozzolanic reactions. The X-ray diffraction technique was unable to detect Fe-oxyhydroxide phase and morealuminosilicate phases in ash core samples due to their low abundance and amorphous character. X-ray fluorescence results of the original ash core samples showed the presence of major oxides, such as SiO2, Al2O3, Fe2O3, while CaO, K2O, TiO2, Na2O, MnO, MgO, P2O5, and SO3 occur in minor concentrations. The ratio of SiO2/Al2O3 classified the original core samples prior to extraction as a silico-aluminate class F fly ash. The ternary plot of major elements in 1-year-old ash core samples was both sialic and ferrocalsialic but 8 year and 20-year-old ash core samples were sialic in chemical composition. It is noteworthy that the mass % of SiO2 varies through the depth of the core with an increase of nearly 3 %, to 58 mass % of SiO2 at a depth of 6 m in the 1-year-old core whereas in the case of the 8-year-old core a 2 % increase of SiO2 to a level of 57.5 mass % can be observed at levels between 4-8 m, showing dissolution of major components in the matrix of older ash cores.. The Na2O content of the Tutuka ash cores was low and varied between 0.6-1.1 mass % for 1-year-old ash cores to around 0.6-0.8 mass % for 8-year-old ash cores. Sodium levels were higher in 1-year-old ash cores compared to 8 year and 20-year-old ashcores. Observed trends indicate that quick weathering of the ash (within a year) leached out Na+ from the ash dump. No evidence of Na+ encapsulation even though the ash dump was brine irrigated. Thus the dry disposal ash placement method does not result in a sustainable salt sink for Na-containing species over time. The total content of each of the elements in 1 year and 20-year-old ash cores was normalised with their total content in fresh ash from same power station to show enrichment and depletion factor. Major elements such as K+, Mn showed enrichment in 1-year-old ash cores whereas Al, Si, Na+, Ti, Ca, Mg, S and Fe showed depletion due to over time erosion. Trace elements such as Cr, Sr, P, Ba, Pb, V and Zn showed enrichment but Ni, Y, Zr showed depletion attributed to over time erosion. In 20-year-old ash cores, major elements such as Al, Na+ and Mn showed enrichment while Si, K+, Fe, Mg and Ca showed depletion highlighting their mobility. Trends indicated intensive flushing of major soluble components such as buffering constituents (CaO) by percolating rain water. The 1-year-old and 20-year-old coal ash cores showed a lower pH and greater loss/depletion of the soluble buffering constituents than the 2-week-old placed ash, indicating significant chemical weathering within a year. Based
on ANC results the leaching behaviours of Ca, Mg, Na+, K+, Se, Cr, and Sr were found to be controlled by the pH of the leachant indicating high mobility of major soluble species in the ash cores when in contact with slightly acid rain water. Other investigated toxic metals such as As, Mo and Pb showed amphoteric behaviour with respect to the pH of the leachant. Chemical alterations and formation of transient minor secondary mineral phases was found to have a significant effect on the acid susceptibility and depletion pattern of chemical species in the core ash samples when compared to fresh ash. These ANC results correlated well with the data generated from the sequential extraction scheme. Based on sequential extraction results elements, showed noticeable mobility in the water soluble, exchangeable and carbonate fractions due to adsorption and desorption caused by variations in the pore water pH. In contrast, slight mobility of elements in the Fe and Mn, and residual fractions of dry disposed fly ashes are attributed to the co-precipitation and dissolution of minor amount of less soluble secondary phase overtime. The 1-year-old dry disposed ash cores were the least weathered among the 3 drilled ash cores. Therefore low concentration of toxic metals in older ash cores were ascribed to extensive weathering with slower release from residual mineral phases over time. Elements were found to associate with different mineral phases depending on the age or depth of the core samples showing greater heterogeneity in dispersion. For instance the average amount of total calcium in different mineral associations of 1-year-old ash cores is as follows
water soluble (10.2 %), exchangeable (37.04 %), carbonate (37.9 %), Fe and Mn (7.1 %) and residual (2.97 %). The amount of total Na+ in different mineral phases of 1-year-old ash cores followed this trend: water soluble (21 %), exchangeable (11.26 %), carbonate (2.6 %), Fe and Mn (4.7 %) and residual (53.9 %). The non-leachable portion of the total Na+ content (namely that contained in the residual fraction) in the 1-year-old ash core samples under conditions found in nature ranged between 5-91 %. This non-leachable portion of the Na+ showed the metastability of the mineral phases with which residual Na+ associates. Results showed older ash cores are enriched in toxic elements. Toxic elements such as As, B, Cr, Mo and Pb are enriched in the residual fraction of older ash cores. For instance As concentration in the residual fraction varied between 0.0003- 0.00043 mg kg-1 for 1-year-old ash cores to around 0.0003-0.0015 mg kg-1 for 20-year-old ash cores. This suggests that the older ash is enriched in toxic elements hence dust from the ash dump would be toxic to human health. The knowledge of mobility and ecotoxicological significance of coal fly ash is needed when considering its disposal or reuse in the environment. The mobility and ecotoxicology of inorganic metals in coal fly ash are determined by (i) mineralogical associations of inorganic species (ii) in-homogeneity in the ash dumps (iii) long and short term exposure to ingress CO2 and percolating rain water. Management issues such as inconsistent placement of ash in the dumps, poor choice of ash dump site, in-homogeneity in brine irrigation, no record of salt load put on the ash dumps and lack of proper monitoring requires improvement. The thesis provides justification for the use of the modified sequential extraction scheme as a predictive tool and could be employed in a similar research work. This thesis also proved that the dry ash disposal method was not environmental friendly in terms of overall leaching potential after significant chemical weathering. Moreover the study proved that the practice of brine co-disposal or irrigation on ash dumps is not sustainable as the ash dump did not act as a salt sink.

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Azevedo, Nuno César Viana. "Applications of random dynamical systems and control in mathematical finance." Doctoral thesis, Instituto Superior de Economia e Gestão, 2014. http://hdl.handle.net/10400.5/7548.

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Doutoramento em Matemática Aplicada à Economia e Gestão
This PhD thesis uses Dynamical Systems, Variational Calculus and Op- timal Control techniques to address three related problems in Mathematical Finance. We start by introducing an alternative characterization for martingale measures in discrete time financial markets models, relating the existence of such measures with a special family of optimization problems. We then move on to address two classical problems in mathematical finance, both connected through the incompleteness of the markets under consideration. We first consider a minimization problem as a model for the interaction between two agents trading a contingent claim in incomplete financial markets (in both discrete-time and continuous-time setups). The agents personal valuations for the contingent claim are assumed to depend on probability measures representing their beliefs concerning the future states of the world, and their goal is to achieve a common price for the contingent claim to be traded, while deviating as little as possible from their initial beliefs. We then prove a dynamic programming principle for a finite horizon optimal control problem for which the state variable dynamics are defined by a Markov- switching jump-diffusion stochastic differential equation. As an application of our results, we study a finite horizon consumption-investment problem in a Markov-switching jump-diffusion financial market.
Nesta Tese de Doutoramento usamos conceitos de Sistemas Dinâmicos, Cálculo Variacional e técnicas de Controlo para lidar com três problemas em Matemática Financeira. Começamos por uma caracterização alternativa das medidas martingale em modelos de mercados financeiros em tempo discreto, relacionando a existência de tal medida com uma família de problemas de optimização. Posteriormente, estudamos dois problemas clássicos em matemática financeira, relacionados pela incompletude dos mercados considerados. O primeiro é um problema de minimização que modela a interação entre dois agentes, que transacionam um derivado financeiro em mercados financeiros incompletos (quer em tempo discreto, quer em tempo contínuo). Assumimos que a avaliação que cada agente faz do derivado financeiro depende de medidas de probabilidade que representam as suas estimativas sobre a probabilidade de ocorrência de cada um dos futuros estados do mundo, e que o seu objetivo consiste em conseguir um preço comum para o derivado financeiro negociado, desviando-se o mínimo possível das suas estimativas iniciais. Finalmente, provamos um princípio de programação dinâmica para um problema de controlo óptimo em horizonte finito, no qual a dinâmica das variáveis de estado é definida por uma equação diferencial estocástica contendo termos de difusão, termos de saltos, sendo, adicionalmente, cada um destes termos modulado por uma cadeia de Markov. Como aplicação estudamos um problema de consumo-investimento em horizonte finito num mercado financeiro formado por activos cuja evolução com o tempo segue uma equação diferencial estocástica do tipo acima descrito.

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Mihoub, Alaeddine. "Apprentissage statistique de modèles de comportement multimodal pour les agents conversationnels interactifs." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAT079/document.

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L'interaction face-à-face représente une des formes les plus fondamentales de la communication humaine. C'est un système dynamique multimodal et couplé – impliquant non seulement la parole mais de nombreux segments du corps dont le regard, l'orientation de la tête, du buste et du corps, les gestes faciaux et brachio-manuels, etc – d'une grande complexité. La compréhension et la modélisation de ce type de communication est une étape cruciale dans le processus de la conception des agents interactifs capables d'engager des conversations crédibles avec des partenaires humains. Concrètement, un modèle de comportement multimodal destiné aux agents sociaux interactifs fait face à la tâche complexe de générer un comportement multimodal étant donné une analyse de la scène et une estimation incrémentale des objectifs conjoints visés au cours de la conversation. L'objectif de cette thèse est de développer des modèles de comportement multimodal pour permettre aux agents artificiels de mener une communication co-verbale pertinente avec un partenaire humain. Alors que l'immense majorité des travaux dans le domaine de l'interaction humain-agent repose essentiellement sur des modèles à base de règles, notre approche se base sur la modélisation statistique des interactions sociales à partir de traces collectées lors d'interactions exemplaires, démontrées par des tuteurs humains. Dans ce cadre, nous introduisons des modèles de comportement dits "sensori-moteurs", qui permettent à la fois la reconnaissance des états cognitifs conjoints et la génération des signaux sociaux d'une manière incrémentale. En particulier, les modèles de comportement proposés ont pour objectif d'estimer l'unité d'interaction (IU) dans laquelle sont engagés de manière conjointe les interlocuteurs et de générer le comportement co-verbal du tuteur humain étant donné le comportement observé de son/ses interlocuteur(s). Les modèles proposés sont principalement des modèles probabilistes graphiques qui se basent sur les chaînes de markov cachés (HMM) et les réseaux bayésiens dynamiques (DBN). Les modèles ont été appris et évalués – notamment comparés à des classifieurs classiques – sur des jeux de données collectés lors de deux différentes interactions face-à-face. Les deux interactions ont été soigneusement conçues de manière à collecter, en un minimum de temps, un nombre suffisant d'exemplaires de gestion de l'attention mutuelle et de deixis multimodale d'objets et de lieux. Nos contributions sont complétées par des méthodes originales d'interprétation et d'évaluation des propriétés des modèles proposés. En comparant tous les modèles avec les vraies traces d'interactions, les résultats montrent que le modèle HMM, grâce à ses propriétés de modélisation séquentielle, dépasse les simples classifieurs en terme de performances. Les modèles semi-markoviens (HSMM) ont été également testé et ont abouti à un meilleur bouclage sensori-moteur grâce à leurs propriétés de modélisation des durées des états. Enfin, grâce à une structure de dépendances riche apprise à partir des données, le modèle DBN a les performances les plus probantes et démontre en outre la coordination multimodale la plus fidèle aux évènements multimodaux originaux
Face to face interaction is one of the most fundamental forms of human communication. It is a complex multimodal and coupled dynamic system involving not only speech but of numerous segments of the body among which gaze, the orientation of the head, the chest and the body, the facial and brachiomanual movements, etc. The understanding and the modeling of this type of communication is a crucial stage for designing interactive agents capable of committing (hiring) credible conversations with human partners. Concretely, a model of multimodal behavior for interactive social agents faces with the complex task of generating gestural scores given an analysis of the scene and an incremental estimation of the joint objectives aimed during the conversation. The objective of this thesis is to develop models of multimodal behavior that allow artificial agents to engage into a relevant co-verbal communication with a human partner. While the immense majority of the works in the field of human-agent interaction (HAI) is scripted using ruled-based models, our approach relies on the training of statistical models from tracks collected during exemplary interactions, demonstrated by human trainers. In this context, we introduce "sensorimotor" models of behavior, which perform at the same time the recognition of joint cognitive states and the generation of the social signals in an incremental way. In particular, the proposed models of behavior have to estimate the current unit of interaction ( IU) in which the interlocutors are jointly committed and to predict the co-verbal behavior of its human trainer given the behavior of the interlocutor(s). The proposed models are all graphical models, i.e. Hidden Markov Models (HMM) and Dynamic Bayesian Networks (DBN). The models were trained and evaluated - in particular compared with classic classifiers - using datasets collected during two different interactions. Both interactions were carefully designed so as to collect, in a minimum amount of time, a sufficient number of exemplars of mutual attention and multimodal deixis of objects and places. Our contributions are completed by original methods for the interpretation and comparative evaluation of the properties of the proposed models. By comparing the output of the models with the original scores, we show that the HMM, thanks to its properties of sequential modeling, outperforms the simple classifiers in term of performances. The semi-Markovian models (HSMM) further improves the estimation of sensorimotor states thanks to duration modeling. Finally, thanks to a rich structure of dependency between variables learnt from the data, the DBN has the most convincing performances and demonstrates both the best performance and the most faithful multimodal coordination to the original multimodal events

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Du, Wei, and 杜為. "The study of online game conflict behaviors—A sequential analysis." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/k3w7r3.

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碩士
中原大學
教育研究所
107
With the development and popularization of technology, human interaction has gradually changed from physical to virtual interaction. This purpose of the study is, through the online game "League of Legends," to understand the causes of network conflicts between players. Currently very few studies analyze the online game conflict behaviors. The purpose of this research is to investigate online game conflict behaviors by applying Bakeman (1986) sequential analysis. The study found that in the conflict behavior of online players, the transition of conflict behavior between players is gradual. When a low degree of conflict occurs, bad communication approaches turned conflicts into high-level conflicts. After comparing online game conflicts with traditional interpersonal conflicts, there is no difference between the two. Because of the characteristics of the network, people are less restricted to social norms in the online world. The research shows the behavior that may not be presented in the interaction between people and people, which leads to more serious conflicts

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"Parent Behaviors and Children's Interest in Play: Examining Behavioral Contingencies for Children with and without Autism." Master's thesis, 2013. http://hdl.handle.net/2286/R.I.20843.

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abstract: The present study examined the behaviors of parents and children during a free play interaction in 20 children with high-functioning autism (HFA) and 20 matched, typically developing children. Observational coding was used to measure sensitive versus controlling parenting behaviors as well as children's responsivity and interest and investment in play. The study also documented whether the child or the parent primarily directed the play interaction. Finally, the study examined the influence of parenting stress on parents' behaviors during play. Group differences in behaviors were assessed along with associations between parent and child behaviors. Further, sequential analyses were conducted to identify whether parent behaviors temporally facilitated children's responses and interest during a play interaction. Results demonstrated group differences in parental sensitivity, parenting stress, child responsivity, and proportion of child-directed play. Parental sensitivity was also associated with child interest and investment as well as the proportion of child-directed play. Finally, sequential analyses demonstrated a temporal association between completely child-directed play and child interest and investment, and between parental sensitivity and child responsivity. These results extend the existing literature on the behaviors of children with autism and those of their parents within play settings, and have important implications for parent-focused play interventions.
Dissertation/Thesis
M.S. Family and Human Development 2013

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Dissertations / Theses on the topic 'Sequential behaviors'

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