Dissertations / Theses on the topic 'Social Choice Function'

Thesis advisor: Uzi Segal<br>This dissertation consists of three chapters analyzing preferences for randomization in social choice problems. The first two chapters are related and in the fields of distributive justice and social choice. They concern allocation of an indivisible good in social choice problems where efficiency is at odds with equality. The last chapter addresses a social choice problem from an individual's perspective using decision theoretical analysis. In this dissertation I demonstrate why randomization may be an attractive policy in social choice problems and demonstrate how individuals may have preferences over the precise method of randomization. The first chapter is titled "Live and Let Die." This paper discusses how to allocate an indivisible good by social lottery when agents have asymmetric claims. Intuition suggests that there may exist agents who should receive zero probability in the optimal social lottery. In such a case, I say that these agents have weak claims to the good. This paper uses a running example of allocating an indivisible medical treatment to individuals with different survival rates and reactions to the treatment in order to provide conditions for consistency of weak claims. As such, I develop two related assumptions on a social planner's preferences over lotteries. The first -- survival rate scaling -- states that if an individual has a weak claim, then his claim is also weak when survival rates increase proportionally. The second -- independence of weak claims -- states that if an individual has a weak claim, then his removal does not affect others' probabilities of receiving the treatment. These assumptions imply that a compatible social welfare function must exhibit constant elasticity of substitution, which results in potentially-degenerate weighted lotteries. The second chapter is titled "Why is Six Afraid of Seven? Bringing the "Numbers" to Economics." This chapter discusses the numbers problem: the question of if the numbers of people involved should be used to determine whether to help certain people or to help certain other people. I discuss the main solutions that have been proposed: flipping a coin, saving the greater number, and proportionally weighted lotteries. Using the economic tools of social choice, I then show how the model of the previous chapter, "Live and Let Die," can be extended to address numbers problems and compare the implications of prominent social welfare functions for numbers problems. I argue that potentially-degenerate weighted lotteries can assuage the main concerns discussed in the literature and I show that both the Nash product social welfare function as well as constant elasticity of substitution (CES) social welfare functions are compatible with this solution. Finally, I discuss a related problem known as "probability cases," in which individuals differ in survival chances rather than numbers of individuals at risk. When the model is extended to allow for both asymmetries in survival chances and numbers of individuals in groups, CES results in potentially-degenerate weighted lotteries whereas Nash product does not. The third chapter is titled "All Probabilities are Equal, but Some Probabilities are More Equal than Others," which is joint work with Professor Uzi Segal of the Economics Department at Boston College and Professor Shlomo Naeh of the Departments of Talmud and Jewish Thought at The Hebrew University of Jerusalem. In this chapter we compare preferences for different procedures of selecting people randomly. A common procedure for selecting people is to have them draw balls from an urn in turn. Modern and ancient stories (for example, by Graham Greene and the Talmud) suggest that such a lottery may not be viewed by the individuals as "fair.'' In this paper, we compare this procedure with several alternatives. These procedures give all individuals equal chance of being selected, but have different structures. We analyze these procedures as multi-stage lotteries. In line with previous literature, our analysis is based on the observation that multi-stage lotteries are not considered indifferent to their probabilistic one-stage representations. As such, we use a non-expected utility model to understand the preferences of risk-averse individuals over these procedures and show that they may be not indifferent between them<br>Thesis (PhD) — Boston College, 2020<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Economics

Examensarbetet handar om språkval Engelska. Mitt intresse väcktes när jag erfor detta kontroversiella ämne som lärarstuderande. Meningen med ämnet är att det är en hjälp för elever som inte klarar av att studera ytterligare ett språk och för elever som behöver extra stöd i engelska. Ämnet har dock misskötts då många elever väljer ämnet utav lathet eller utav taktiska skäl. Iden med att endast låta de elever som som verkligen behöver extra stöd i engelska har förlorats. Jag har utfört intervjuermed sex olika lärare på fyra olika skolor angående hur språkval engelska är organiserat. Alla skolor har olika organisationer. Jag använde mig av formella intervjuer. Resultatet av dessa var att organisationen fungerar olika bra på de olika skolorna. Orsakerna till detta är många. På de skolor där det inte fungerar lika bra anges orsaker så som att ämnet har låg status, stora heterogena grupper och lärare och elever som är omotiverade.<br>This dissertation deals with what in Swedish schools is called ”Språkval Engelska”. It will be refered to as Language Choice English in the ongoing text. My interest was aroused after having experienced this controversial subject as a student teacher. I found that different schools work with the subject in different ways. There is no clear syllabus for the subject since the grading is a part of the ordinary English grade. Language Choice English is an option for those who do not want to choose French, German or Spanish as Language Choice. The idea is that the subject is meant for those who cannot cope with yet another language and who need extra support in English. This study shows that not only the so-called weak pupils choose to study Language Choice English. There has been a mismanagement of the subject since so many pupils who are good at English choose it out of convenience and for tactical reasons. The idea of only letting those pupils, who actually need more support choose it, has been lost. Four different secondary schools have been investigated concerning how Language Choice English is organized. I learned that all of these schools have different organizations. The method I used was formal interviews with six different teachers at four different schools. The results of the interviews show that at some schools the subject works well. At other schools it does not. The reasons for this seem to be many. Reasons such as low status of the subject, large and heterogeneous groups and pupils and teachers who are unmotivated can be mentioned.

Dada a grande quantidade de dados gerados atualmente, apenas uma pequena porção dos mesmos pode ser rotulada manualmente por especialistas humanos. Isso é um desafio comum para aplicações de aprendizagem de máquina. Aprendizado semi-supervisionado aborda este problema através da manipulação dos dados não rotulados juntamente aos dados rotulados. Entretanto, se apenas uma quantidade limitada de exemplos rotulados está disponível, o desempenho da tarefa de aprendizagem de máquina (e.g., classificação) pode ser não satisfatória. Diversas soluções abordam este problema através do uso de uma ensemble de classificadores, visto que essa abordagem aumenta a diversidade dos classificadores. Algoritmos como o co-training e o tri-training utilizam múltiplas partições de dados ou múltiplos algoritmos de aprendizado para melhorar a qualidade da classificação de instâncias não rotuladas através de concordância por maioria simples. Além disso, existem abordagens que estendem esta ideia e adotam processos de votação menos triviais para definir os rótulos, como eleição por maioria ponderada, por exemplo. Contudo, estas soluções requerem que os rótulos possuam um certo nível de confiança para serem utilizados no treinamento. Consequentemente, nem toda a informação disponível é utilizada. Por exemplo: informações associadas a níveis de confiança baixos são totalmente ignoradas. Este trabalho propõe uma abordagem chamada social-training, que utiliza toda a informação disponível na tarefa de aprendizado semi-supervisionado. Para isto, múltiplos classificadores heterogêneos são treinados com os dados rotulados e geram diversas classificações para as mesmas instâncias não rotuladas. O social-training, então, agrega estes resultados em um único rótulo por meio de funções de escolha social que trabalham com agregação de rankings sobre as instâncias. Especificamente, a solução trabalha com casos de classificação binária. Os resultados mostram que trabalhar com o ranking completo, ou seja, rotular todas as instâncias não rotuladas, é capaz de reduzir o erro de classificação para alguns conjuntos de dados da base da UCI utilizados.<br>Given the huge quantity of data currently being generated, just a small portion of it can be manually labeled by human experts. This is a challenge for machine learning applications. Semi-supervised learning addresses this problem by handling unlabeled data alongside labeled ones. However, if only a limited quantity of labeled examples is available, the performance of the machine learning task (e.g., classification) can be very unsatisfactory. Many solutions address this issue by using a classifier ensemble because this increases diversity. Algorithms such as co-training and tri-training use multiple views or multiple learning algorithms in order to improve the classification of unlabeled instances through simple majority agreement. Also, there are approaches that extend this idea and adopt less trivial voting processes to define the labels, like weighted majority voting. Nevertheless, these solutions require some confidence level on the label in order to use it for training. Hence, not all information is used, i.e., information associated with low confidence level is disregarded completely. An approach called social-training is proposed, which uses all information available in the semi-supervised learning task. For this, multiple heterogeneous classifiers are trained with the labeled data and generate diverse classifications for the same unlabeled instances. Social-training then aggregates these results into a single label by means of social choice functions that work with rank aggregation over the instances. The solution addresses binary classification cases. The results show that working with the full ranking, i.e., labeling all unlabeled instances, is able to reduce the classification error for some UCI data sets used.

Made available in DSpace on 2016-08-10T10:46:46Z (GMT). No. of bitstreams: 1 RICARDO AGUIAR BARROS.pdf: 915982 bytes, checksum: eb7975f43af665b70148e32e7eefd0fa (MD5) Previous issue date: 2012-08-17<br>This work is linked to the research line "International Relations" of the Master's program in Law, International Relations and Development from the Catholic University of Goiás analyzes the principle of autonomy of the contracting parties in a private international relations, as well as principles that encourage entrepreneurship and free enterprise and protect the company, as a figure in primary production and growth of a country. The Brazilian Civil Code of 2002 brought a number of principles that guide and delimit the will of the parties at the time of hiring, the execution of contracts and completion / termination thereof. Hence the study of national and international contracts, laws applicable to the institute and understanding of freedom of choice of contractors and their limits imposed by international conventions of The Hague, Vienna and Rome and by UNIDROIT and the cases and trial of the major conflicts .<br>Esta dissertação vincula-se à linha de pesquisa "Relações Internacionais" do programa de Mestrado em Direito, Relações Internacionais e Desenvolvimento pela Pontifícia Universidade Católica de Goiás. Analisa o princípio da autonomia da vontade das partes contratantes em uma relação internacional privada, bem como o empreendedorismo como princípios que incentivam a livre iniciativa e a proteção a empresa, como figura primordial na proteção e crescimento de um país. O Código Civil brasileiro de 2002 trouxe vários princípios que norteiam e delimitam a vontade dos contratantes no momento de contratar, na execução dos contratos e na conclusão/extinção dos mesmos. Daí o estudo dos contratos nacionais e internacionais, as leis aplicáveis ao instituto e a compreensão da autonomia da vontade dos contratantes e seus limites impostos pelas convenções internacionais de Haia, de Viena e de Roma e pela UNIDROIT bem como os casos concretos e julgados dos principais conflitos.

As informações acerca da performance e impacto socioambientais do fornecedor e do produto são necessárias para o exercício do consumo de forma sustentável. O conhecimento dos impactos socioambientais advindos da produção, uso e pós-consumo é requisito para a livre escolha dos consumidores por produtos que apresentem impactos socioambientais positivos em qualquer dessas fases de seu ciclo de vida. Um dos instrumentos para o alcance do desenvolvimento sustentável é possibilitar o consumo de produtos que utilizem menos recursos finitos da natureza e que tragam melhorias sociais como suas consequências. No Brasil, o fundamento para a inclusão dos dados socioambientais do produto nas informações veiculadas ao consumidor está presente no ordenamento jurídico, na garantia de acesso à informação e no direito à preservação do meio ambiente, ambos inseridos no rol dos direitos constitucionais fundamentais, ao lado do princípio da dignidade da pessoa humana, bem como em preceitos do Código de Defesa do Consumidor e da legislação ambiental. A função social da empresa decorrente do princípio constitucional da função social da propriedade também justifica o dever de veiculação dos dados referentes ao impacto socioambiental de seus produtos e acerca do comportamento socioambiental da empresa. A veiculação desses dados beneficia a concorrência, acarretando o aperfeiçoamento dos próprios meios de produção para atrair os consumidores que optam por produtos sustentáveis. Os deveres de clareza e veracidade, decorrentes do princípio da boa-fé objetiva previstos no CC e CDC, necessitam ser observados na veiculação dessas informações para evitar a maquiagem socioambiental, que é a divulgação da falsa imagem de preocupação socioambiental ao produto. A essencialidade ou utilidade das informações é o parâmetro para sua veiculação sob o risco de ocorrer seu excesso, que impede a correta compreensão de todos os dados apresentados. Até os riscos de impactos socioambientais ainda não comprovados cabem ser informados em atenção ao princípio da precaução. O repasse dessas informações pode e deve ocorrer por todos os meios de comunicação utilizados para a divulgação dos produtos, ressaltando-se o papel da rotulagem.<br>The information concerning the social-environmental impact of the product and the of the producers performance are necessary for the exercise of the sustainable consumption. The knowledge of the social-environmental impacts of the life cycle impact of the product is a requisite for the free choice of the consumers for products that present positive social-environmental impacts in any of these phases of its cycle of life. One of the instruments for the reach of the sustainable development is to make possible the consumption of products that use less finite resources of the nature and that they bring social improvements as its consequences. In Brazil, is possible to conclude that the legal system establishes the inclusion of the social-environmental data of the product in the information propagated to the consumer. Brazilian Constitution imposes the guarantee of access to the information, the consumer protection and the right of the preservation of the environment, as well as the dignity of the person human being. The social function of the companies, based in the constitutional principle of the social function of the property also justifies the duty of propagation of the referring data to the social-environmental impact of its products and concerning the social-environmental behavior of the company. In the legislative basis, there are strong rules concerning information in the Code of Defense of the Consumer and the environmental legislation. The propagation of these data benefits to the competition, creating incentives to the companies improving the means of production to attract the consumers that opt to sustainable products. The duties of clarity and veracity, attached with the good-faith principle established by Civil Code and Consumer Defense Code, need to be observed in the propagation of this information to prevent the greenwashing, that it is the propagation of the false image of social-environmental concern to the product. The essentiality or utility of the information is the parameter for its propagation under the risk to occur its excess, which hinders the correct understanding of all the presented data. Until the risks of social-environmental impacts not yet proven, they fit to be informed in attention to the Precautionary Principle. The view of this information can and must occur by all means of communication used for the spreading of the products, standing out itself the paper of the labeling.

Diese Dissertation untersucht verschiedene soziale sowie landschaftsästhetische Funktionen der Landwirtschaft in strukturell gegensätzlichen Agrarsystemen. In der Untersuchung wird hierfür stets ein von kleinen Familienbetrieben dominiertes System mit einem stärker großstrukturierten, gewerblichen System verglichen. Die Arbeitszufriedenheit der Landwirte sowie ihre soziale Vernetzung mit der lokalen Gemeinde wurden im Vergleich zwischen dem kleinbäuerlichen Schweizer und dem großbetrieblichen nordostdeutschen System analysiert. Mittels Choice Experimenten wurden in der Schweiz und in Süddeutschland (d.h. kleinbäuerliche Systeme) sowie in Ostdeutschland (d.h. großstruktiertes, gewerbliches System) zudem Bevölkerungspräferenzen für Agrarlandschaften und damit die ästhetische Funktion der Landwirtschaft untersucht. Unter Berücksichtigung der Betriebsstruktur (z.B. Betriebsgröße) sind Schweizer Bauern zufriedener mit ihrer Arbeit als nordostdeutsche. Das Betriebseinkommen ist für nordostdeutsche Bauern signifikant wichtiger für die Arbeitszufriedenheit als für die Schweizer Kollegen. Besonders für Schweizer Bauern spielt die Betriebsdiversifizierung eine positive Rolle für die Zufriedenheit, z.B. die Vielfalt der Produktionszweige oder nicht-landwirtschaftliche Betriebszweige wie Agrotourismus. Auch haben Schweizer Bauern und solche kleinerer Betriebe mehr Bezug zu ihrer lokalen Gemeinde durch lokal fokussierte soziale Netzwerke. Betriebsleiter größerer Betriebe sind hauptsächlich außerhalb der Gemeinden vernetzt und fühlen sich diesen weniger zugehörig. Zudem stärkt ein biographischer Bezug zum Hof die Verbindung mit der Gemeinde. Die Mehrheit der befragten Schweizer und Ostdeutschen ist zudem für qualitative Veränderungen der Agrarlandschaften (d.h. mehr Weiden zur Freilandhaltung, Streuobstwiesen und höhere Biodiversität). Waldrückgange sowie Schlaggrößenveränderungen landwirtschaftlicher oder forstlicher Flächen werden nahezu einheitlich abgelehnt.<br>This dissertation investigates different social functions of agriculture as well as landscape aesthetics in farming systems of different agricultural structures. Throughout the whole project farming systems dominated by small family farms and large-scale farming systems dominated by commercial non-family farms (e.g. cooperatives) were compared. Farmers’ work satisfaction and their connection to the local community were examined in the small-scaled Swiss system and in the larger scaled Northeast (NE) German one. Public landscape preferences were derived using choice experiments in Switzerland and South Germany, representing small-scale systems, as well as in East Germany, representing a large-scaled one, to explore agriculture‘s aesthetic function. Swiss farmers are more satisfied with their agricultural work if for effects of farm structure (e.g. farm size) is controlled for. Farm income plays a significantly more important role for the work satisfaction of NE German farmers than for that of Swiss ones. Especially for Swiss farmers, farm diversification plays an important role, for example through a diversity of production lines or through non-agricultural activities like agrotourism. Further results show that Swiss farmers and farmers of smaller farms are more connected to their local communities through more locally focused social networks. Farmers of larger farms have their networks farther away from the farm and a weaker sense of belonging to their local community. A biographical bond to the farm also strenghtens the connection to the local community. Concerning public landscape preferences the majority of the Swiss and East German respondents generally prefers qualitative changes to landscapes (i.e. meadows for free range animal husbandry, meadow orchards and more biodiversity). Forest loss or changes in plot sizes of agricultural land and forests are nearly uniformly rejected in all regions.

Physical activity is essential for children and adults to counteract the negative health outcomes related to a sedentary lifestyle. Despite widely publicized recommendation and information about physical activity the problem of excessive physically inactivity prevails in our society. The purpose of this study was to conduct a context functional analysis to identify outdoor activity contexts that engendered higher levels of MVPA and to adopt Dunlap, DePerczel, Clarke, Wilson, Wright, White, and Gomes’ (1994) methodology by utilizing an ABAB reversal design to determine if choice making influences levels of moderate-to-vigorous physical activity (MVPA) in six preschool-aged children. Results of the context functional analysis showed that fixed equipment and open space engendered highest levels of MVPA in most participants. Levels of MVPA in the reversal design indicated that choice did not significantly influence levels of MVPA and that healthy and unhealthy choices varied between and within participants. These results suggest that related to levels of MVPA the type of outdoor activity context chosen is more important than the individual who chooses it.

Made available in DSpace on 2015-05-14T13:16:34Z (GMT). No. of bitstreams: 1 arquivototal.PDF: 1526331 bytes, checksum: 38e40aec6b111371aebd1a5cba081a3c (MD5) Previous issue date: 2009-04-27<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES<br>Epilepsy is a brain dysfunction characterized by the repeated tendency of the brain to cause epileptic crisis and by the neurobiological, cognitive, psychological and social consequences of this condition. In these terms, the aim of this work is to determine the visual sensory threshold of children and adolescents who have and who do not have epilepsy, analyzing possible alterations in the form related to this dysfunction. The sensory threshold is defined as the smallest intensity of incentive a human being is capable of detecting. The contrast sensitivity function (CSF) is the inverse of the threshold curve of contrast (1/CSF). This way, the CSF is a tool that allows us to label the answer of SV to visual patterns in low, medium and high levels of contrast and evaluate possible sensorial alterations associated with the visual processing. The main idea is that the elevation or reduction of the CSF can happen deem to sensorial, cognitive and behavioral alterations. Twenty volunteers participated on this study, from both genders, between 7 and 17 years of age, 10 of whom nonepileptic and 10 epileptic (tonic-clonic crisis). All of them presented either normal or corrected visual accuracy and were distributed in groups that were equivalent in age. The resolutions were taken from the psychophysical forced-choice method, using the static sine wave gratings with spatial frequencies of 0.25, 2.0 and 8.0 cpd (cycles per degree of visual angle). During each experimental session, there were stimulus pares presented randomly (test stimulus and neutral), and the task of the participants was to choose always the test stimulus with one of the frequencies above. The criterion used was the one of three consecutive correct answers to low the contrast in one unity and just one mistake to increase the contrast in the same unity (20%). After each session, a sheet of results with the experimental situation was released and the six values of contrast were calculated by the reversions. The values of contrast obtained to each frequency were grouped in spreadsheets separated by condition (with or without epilepsy) and the big average was used as an estimative of the sensory threshold or of the sensibility to the contrast due to each spatial frequency tested. The analysis of variance (ANOVA) to repeated measures showed significant differences between the groups [F(1,238) = 11.80); p<0.01]. The analysis obtained with the help of the test posthoc Tukey HSD revealed a relevant dissimilarity only in the 0.25cpg (p<0.01)]. In other words, the results indicated an expressive alteration in the visual perception children and adolescents with epilepsy have.<br>A epilepsia é um distúrbio cerebral caracterizado pela predisposição persistente do cérebro para gerar crises epilépticas e pelas conseqüências neurobiológicas, cognitivas, psicológicas e sociais desta condição. Algumas pesquisas demonstram que distúrbios visuais são bastante freqüentes em pessoas com epilepsia. Nestes termos, o objetivo deste trabalho foi determinar o limiar sensório visual de crianças e adolescentes com e sem epilepsia, verificando possíveis alterações na percepção visual da forma relacionadas a este transtorno. O limiar sensório é definido como a menor intensidade de um estímulo que um ser humano é capaz de detectar. A função de sensibilidade ao contraste (FSC) é o inverso da curva de limiar de contraste (1/FSC). Assim, a FSC é uma ferramenta que permite caracterizar a resposta do SV para padrões visuais em níveis baixos, médios e altos de contraste e avaliar possíveis alterações sensoriais relacionadas ao processamento visual. A idéia principal é que a elevação ou redução da FSC pode está relacionada a alterações sensoriais, cognitivas e comportamentais. Participaram deste estudo, 20 voluntários de ambos os sexos com idades entre 7 e 17 anos, sendo 10 sem epilepsia e 10 com epilepsia (crises tônicoclônicas). Todos apresentavam acuidade visual normal ou corrigida e foram distribuídos pelos grupos atendendo ao critério de equivalência de idade. As medidas foram realizadas com o método psicofísico da escolha forçada, utilizando grade senoidal vertical estática com freqüências espaciais de 0,25; 2,0 e 8,0 cpg (ciclos por grau de ângulo visual). Durante cada sessão experimental, foram apresentados aleatoriamente pares de estímulos (estímulo de teste e neutro), e a tarefa dos participantes foi escolher sempre o estímulo de teste com uma das freqüências acima. O critério adotado foi o de três acertos consecutivos para diminuir o contraste em uma unidade, e apenas um erro para aumentar o contraste na mesma unidade (20%). Após cada sessão, o programa produzia uma folha de resultados com a situação experimental e os seis valores de contraste conseguidos pelas reversões. Os valores de contraste obtidos para cada freqüência foram agrupados em planilhas por condição (com e sem epilepsia) e a grande média foi utilizada como estimativa do limiar sensório ou da sensibilidade ao contraste em função de cada freqüência espacial testada. A análise de variância (ANOVA) para medidas repetidas mostrou diferenças significantes entre os dois grupos [F(1, 238) =11,80); p < 0,01]. Já a análise com o teste post-hoc Tukey HSD revelou diferença significante apenas na faixa de freqüências de 0,25 cpg (p < 0,01). Em termos gerais, os resultados demonstraram alteração significante na percepção visual da forma de crianças e adolescentes com epilepsia.

Low levels of physical activity are correlated with negative health outcomes such as heart disease, diabetes, and certain types of cancer. This is concerning given the current rise in obesity and physical inactivity, especially in young children. Developing assessments that can readily identify variables related to unhealthy patterns of activity might be useful in informing interventions that aim to increase physical activity. The current study extended previous research in the functional analysis of physical activity by Hustyi, Normand, and Larson (2012) by evaluating the utility of a choice assessment procedure to identify participant preference to several common outdoor activity contexts, typically available during school recess. Together, the two assessments strategies were able to identify both healthy and less healthy patterns of responding in four preschool-age children. The information obtained from these assessments could be used to inform behavioral interventions that aim to increase physical activity in young children.

Humans are unique in their ability to flexibly and rapidly adapt their behaviour and select courses of action that lead to future reward. Several ‘component processes’ must be implemented by the human brain in order to facilitate this behaviour. This thesis examines two such components; (i) the neural substrates supporting action selection during value- guided choice using magnetoencephalography (MEG), and (ii) learning the value of environmental stimuli and other people’s actions using functional magnetic resonance imaging (fMRI). In both situations, it is helpful to formally model the underlying component process, as this generates predictions of trial-to-trial variability in the signal from a brain region involved in its implementation. In the case of value-guided action selection, a biophysically realistic implementation of a drift diffusion model is used. Using this model, it is predicted that there are specific times and frequency bands at which correlates of value are seen. Firstly, there are correlates of the overall value of the two presented options, and secondly the difference in value between the options. Both correlates should be observed in the local field potential, which is closely related to the signal measured using MEG. Importantly, the content of these predictions is quite distinct from the function of the model circuit, which is to transform inputs relating to the value of each option into a categorical decision. In the case of social learning, the same reinforcement learning model is used to track both the value of two stimuli that the subject can choose between, and the advice of a confederate who is playing alongside them. As the confederate advice is actually delivered by a computer, it is possible to keep prediction error and learning rate terms for stimuli and advice orthogonal to one another, and so look for neural correlates of both social and non-social learning in the same fMRI data. Correlates of intentional inference are found in a network of brain regions previously implicated in social cognition, notably the dorsomedial prefrontal cortex, the right temporoparietal junction, and the anterior cingulate gyrus.

Made available in DSpace on 2016-04-28T18:23:45Z (GMT). No. of bitstreams: 1 Silmara Parise Barosa.pdf: 292799 bytes, checksum: eddb06ac810214162de05d3f6460cd04 (MD5) Previous issue date: 2008-05-27<br>This research examines the casual conversation of children between the ages of five and six within social interactions in pretend plays. Herein, I show how a number of researchers face pretend play, its relevance to the child´s development and the importance of this experience to the nuclear self I attempt, at first, to point out the importance of social interaction, in this context, to the improvement of the child´s linguistic skills; secondly, I try to highlight the lexicogrammatical choices made by these children when setting the limits between reality and fantasy, those that reveal their pragmatic competence. For this reason, I fall back upon the theoretical frame of Functional Systemic Linguistics (Halliday 1994), with special emphasis on the interpersonal metafunction and also on casual conversation (Eggins & Slade, 1997). The analyses embrace the acts of speech, lexicogrammatical choices and pragmatic competence. The results suggest that five-to-six-year-old children are capable of providing information exchange and posing challenges for the negotiation of power during pretend play, and that the fantasy context is propitious for interaction practice, without the presence of an adult. Note the intertext that sets a new social and cultural context based on the relationship of values and beliefs that the interactants bring from their family circle. The construction of the social self involves the recognition of social roles and the assignment of these roles among the participants. The marking of the reality and fantasy reference frames is realized through verbs in the present and past tenses in all the analyzed texts, and the findings of Musatti & Orsolini (1993); Lodge (1979); Kaper (1980); James (1982) e Van Gessel-Hotcker (1989) corroborate it. In addition, the analyses show the children´s competence concerning the use of pragmatic features of language when it comes to the structural dimensions related to the turn-taking dynamics; social, as the mutual intention to topics of conversation; cognitive, as the interactants communicative intention; and linguistic, as the use of speech markers, verbs, and pronouns to connect<br>Este trabalho examina a conversa casual de crianças de 5 a 6 anos de idade em contextos de interação social na brincadeira de faz-de-conta. Mostro como os vários pesquisadores encaram a brincadeira de faz-de-conta, sua relevância para o desenvolvimento infantil e a importância dessa experiência para a formação do eu nuclear. Tento, em um primeiro momento, destacar a importância da interação social nesse contexto para o crescimento das habilidades lingüísticas da criança; em um segundo momento, tento ressaltar as escolhas léxico-gramaticais feitas pelas crianças ao marcar os limites entre a realidade e a fantasia, aquelas que denunciam sua competência pragmática. Para tanto, recorro ao arcabouço teórico da Lingüística Sistêmico Funcional (Halliday 1994), com especial enfoque na metafunção interpessoal, e também sobre a conversa casual (Eggins & Slade, 1997). As análises abrangem os atos de fala, as escolhas léxico-gramaticais e a competência pragmática. Os resultados sugerem que as crianças da faixa etária de 5 a 6 anos são capazes de proporcionar a troca de informações e oferecer desafios para a negociação do poder durante o jogo de faz-de-conta, e que o contexto de fantasia é propício ao exercício da interação, sem a presença do adulto. Note-se o intertexto que redesenha um contexto social e cultural baseado na filiação dos valores e crenças que os interactantes trazem do ambiente familiar e que constituem o contexto em que ocorrem as interações. A construção do eu social, envolve o reconhecimento de papéis sociais e a atribuição desses papéis entre os participantes. A marcação dos enquadres de referência da realidade e da fantasia é realizada pelo tempo verbal no presente e no pretérito, em todos os textos analisados, e corroboram os achados de (Musatti & Orsolini (1993); Lodge (1979); Kaper (1980); James (1982) e Van Gessel-Hotcker (1989) em uma perspectiva interlingüística. As análises revelam, ainda, a competência das crianças quanto ao uso de aspectos pragmáticos da linguagem nas dimensões da estrutura discursiva, como a dinâmica de tomada de turno; social, como a atenção mútua aos tópicos da conversa; cognitiva, como as intenções comunicativas dos interactantes; e lingüística, como o uso de marcadores de discurso, verbos, e pronomes para conectar as idéias

La maladie de Huntington s’accompagne de troubles des conduites sociales perturbant les relations interindividuelles. L'objectif de ce travail de thèse était de mieux comprendre ces troubles sociaux en examinant les habiletés en cognition sociale de personnes porteuses de la mutation ou atteintes de cette maladie neurogénétique. La cognition sociale comprend notamment la reconnaissance des émotions d’autrui, les connaissances sociales et la théorie de l’esprit, soit la capacité à attribuer aux autres des états mentaux affectifs (sentiments) ou cognitifs (intentions,croyances). Nous avons étudié la cognition sociale à la phase présymptomatique et symptomatique de la maladie de Huntington à l’aide de tests neuropsychologiques et de la neuroimagerie morphologique et fonctionnelle. Ce travail a été réalisé dans le cadre d’une collaboration entre le centre national de référence pour les maladies neurogénétiques de l'adulte du CHU d’Angers et la plate-forme d’imagerie médicale Cyceron de Caen. Ce travail visait à mieux comprendre les perturbations en cognition sociale accompagnant la maladie de Huntington, leur évolution et leurs bases neurobiologiques afin d’améliorer notre compréhension des troubles du comportement accompagnant cette maladie. Nous espérons ainsi pouvoir mieux contribuer au diagnostic, au pronostic et à la prise en charge des personnes concernées par cette maladie<br>Huntington's disease is accompanied by disturbances insocial behavior that disrupt inter-individual relationships.The aim of this thesis was to better understand these social disorders by examining the social cognition skills of people with the mutation or the neurogenic disease. Social cognition includes the recognition of the emotions of others, social knowledge and the theory of the mind, namely the ability to attribute to others emotional (feelings) or cognitive (intentions, beliefs) mental states. We studied social cognition in the presymptomatic and symptomatic phase of Huntington's disease using neuropsychological tests and morphological and functional neuroimaging. This work was carried out within the framework of a collaboration between the national center of reference for the neurogenic diseases of adults of the CHU of Angers and the platform of medical imaging Cyceron of Caen. This work aimed to better understand the social cognition disruptions accompanying Huntington's disease, their evolution and their neurobiological basis in order to improve our understanding of behavioral disorders accompanying this disease. We hope to be able to better contribute to the diagnosis, prognosis and care of those affected by this disease

The on-line advertising market involving displaying of Ads against search results by a search engine is growing at a fast rate. A majority of the search engine companies sell their advertising space through auctions which are popularly called sponsored search auctions. In the face of fierce competition, each search engine company faces the threat of its advertisers switching to an alternative search engine in quest of better bang-per-buck. In order to retain customers, the search engine companies have introduced many utilities such as bid optimizer, ad slotting, and budget optimizer to promise enhanced bang-per-buck to the advertisers. The focus of this work is on the bid optimizer which is a software agent that automatically chooses bid values on behalf of the bidders. Bidders will provide a target budget to exhaust and a maximum bid value (willingness to pay). The bid optimizer aims to maximize the bang-per-buck by adjusting the bid amount based on the projected keyword traffic and remaining budget. In this thesis, we develop a novel bid optimizer based on Nash bargaining theory. The thesis is in two parts. In the first part, we address continuous bids while in the second part, we address discrete bids. Our formulation consists of a two person Nash bargaining model, where, the auctioneer is one player and a virtual aggregated agent representing all the n bidders is the other player. In the continuous bids case, the Nash bargaining formulation leads to a convex hull of the utility space of these two players. We show that this convex hull has exactly three corner points which can be computed in O(nlogn) time. Next, we show that the Nash bargaining solution, a point in this convex hull can be mapped to a bid profile of the bidders in O(n) time. Such a bid profile happens to be a local envy-free equilibrium of the underlying game that gets induced among the bidders due to the combined effect of auction rules and the bid optimizer. In the discrete bids case, we show that the Nash bargaining solution always lies on a certain edge of the convex hull such that one end point of the edge is the vector of maximum willingness to pay of all the bidders. We show that the other endpoint of this edge can be computed as a solution of a linear programming problem. We also map this solution to a bid profile of the bidders. For both continuous bids and discrete bids, we describe an algorithmic approach for implementing our idea. We also show experimentally that the proposed bid optimization algorithm, in conjunction with the generalized second price (GSP) auction as the underlying mechanism, outperforms the GSP when we take into account the realistic possibility of bidders dropping from the auction.

abstract: Borda's social choice method and Condorcet's social choice method are shown to satisfy different monotonicities and it is shown that it is impossible for any social choice method to satisfy them both. Results of a Monte Carlo simulation are presented which estimate the probability of each of the following social choice methods being manipulable: plurality (first past the post), Borda count, instant runoff, Kemeny-Young, Schulze, and majority Borda. The Kemeny-Young and Schulze methods exhibit the strongest resistance to random manipulability. Two variations of the majority judgment method, with different tie-breaking rules, are compared for continuity. A new variation is proposed which minimizes discontinuity. A framework for social choice methods based on grades is presented. It is based on the Balinski-Laraki framework, but doesn't require aggregation functions to be strictly monotone. By relaxing this restriction, strategy-proof aggregation functions can better handle a polarized electorate, can give a societal grade closer to the input grades, and can partially avoid certain voting paradoxes. A new cardinal voting method, called the linear median is presented, and is shown to have several very valuable properties. Range voting, the majority judgment, and the linear median are also simulated to compare their manipulability against that of the ordinal methods.<br>Dissertation/Thesis<br>Ph.D. Mathematics 2010

碩士<br>真理大學<br>經濟學系財經碩士班<br>107<br>Taking another angle to explore society when there are only two people and their preferences completely opposite, what form of social choice function can it be rationalized by the game tree? Firstly, it can be proved that any social choice function that conforms to linear ordering can be rationalized by two-person who with opposite preferences by game tree. It is worth noting that this is true for any number of alternatives. Second, to further sort out the example of "three alternatives in society", at this point, the social choice function has 24 possibilities, including linear ordering and looping. We proved all forms of social choice function can be the opposite preference of the two but not limited to the same two people rationalized by the game tree. Furthermore, even if the opposite preference of the two but limited to the same two people, as long as you face three alternatives at the same time, the social choice function is an option to choose a two-person ordering compromise, even a looping type of social choice function also can be rationalized by the game tree composed of the opposite preference of the two but limited to the same two people. So a social choice function that can be rationalized by the two people with the opposite preference use game tree not limited to the form of linear ordering, whether the conclusion of "two people, three alternatives" can be extended to any number of alternatives still requires follow-up research.

碩士<br>國立新竹教育大學<br>音樂學系音樂教師碩士在職專班<br>103<br>With the advances in medicine, the average ages of people increasing gradually. To encourage citizen keep learning, our government actively plans many courses for adult education, lifelong education, seniors education, community college..and so on. Join choir is one of learning courses can brings everyone to pursuit a quality life with no ages limitation. Yang Xin choir was established over thirteen year ago, the average age of members about 60 years old, I practice by joining many music activities, and arrange structured and semi-structured questionnaire to interview the way to understand the interaction between the chorus and the people, and records what benefits that choir brings to people, and further more to the social. The results show choir not only promote the personal artistic humanities, physical and mind health, but also forming a cooperation power among members virtually, especially for those retired members, singing can make them happy, and they present their concern via the songs, and find their self recognition. The charming power also affect the people around them and attract people around them to join together. In addition to the musical activities in the value of the activity itself, it should also have personal values and community values, family values and social function values, such as links with the community to create a phase, Moreover, it can promote a sense of community, community identity, community learning, and bring a happiness and joyful life.

The research in the field of travel demand modeling is driven by the need to understand individuals’ behavior in the context of travel-related decisions as accurately as possible. In this regard, the activity-based approach to modeling travel demand has received substantial attention in the past decade, both in the research arena as well as in practice. At the same time, recent efforts have been focused on more fully realizing the potential of activity-based models by explicitly recognizing the multi-dimensional nature of activity-travel decisions. However, as more behavioral elements/dimensions are added, the dimensionality of the model systems tends to explode, making the estimation of such models all but infeasible using traditional inference methods. As a result, analysts and practitioners often trade-off between recognizing attributes that will make a model behaviorally more representative (from a theoretical viewpoint) and being able to estimate/implement a model (from a practical viewpoint). An alternative approach to deal with the estimation complications arising from multi-dimensional choice situations is the technique of composite marginal likelihood (CML). This is an estimation technique that is gaining substantial attention in the statistics field, though there has been relatively little coverage of this method in transportation and other fields. The CML approach is a conceptually and pedagogically simpler simulation-free procedure (relative to traditional approaches that employ simulation techniques), and has the advantage of reproducibility of the results. Under the usual regularity assumptions, the CML estimator is consistent, unbiased, and asymptotically normally distributed. The discussion above indicates that the CML approach has the potential to contribute in the area of travel demand modeling in a significant way. For example, the approach can be used to develop conceptually and behaviorally more appealing models to examine individuals’ travel decisions in a joint framework. The overarching goal of the current research work is to demonstrate the applicability of the CML approach in the area of activity-travel demand modeling and to highlight the enhanced features of the choice models estimated using the CML approach. The goal of the dissertation is achieved in three steps as follows: (1) by evaluating the performance of the CML approach in multivariate situations, (2) by developing multidimensional choice models using the CML approach, and (3) by demonstrating applications of the multidimensional choice models developed in the current dissertation.<br>text