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Tesi sul tema "Choice modelling"
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1
Jenkinson, Barbara. "Choice modelling with green choices". Thesis, Glasgow Caledonian University, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.688268.
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Boccara, Bruno 1956. "Modelling choice set formation in discrete choice models". Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/14324.
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Lukban, Albert. "Discrete choice modelling in conjoint analysis". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0005/MQ44211.pdf.
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Lukban, Albert. "Discrete choice modelling in conjoint analysis". Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=20582.
Testo completoAbstract (sommario):
Strategic planning is not only necessary in today's global economy where markets are becoming more susceptible to international competition, it is vital. The foresight of market reactions can lead to a competitive advantage. Market share losses can be minimized (and market share gains maximized) with the knowledge obtained from primary marketing research involving a stated preference study to examine consumer behaviour. Before launching a new product or providing a service, discrete choice analysis can empower strategic planners, managers and marketers with a tool which aids in optimizing products and services for a potential market with the end of maximizing sales and services.Discrete choice analysis is a tool to understand human choice behaviour. It is employed for statistical inference on a model of choice behaviour from data obtained by sampling from a population of decision makers. This thesis gives an overview of the basic concepts of conjoint analysis which addresses discrete choice analysis for strategic product and service planning. The statistical model specification, the multinomial logit, is derived assuming that decision makers follow a choice rule called utility maximization, where these random utilities are Gumbel distributed. The model is applied to a stated preference study in which environmentally friendly vehicles are presented as possible vehicle choices.
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Hole, Arne Risa. "Modelling commuters' mode choice in Scotland". Thesis, University of St Andrews, 2005. http://hdl.handle.net/10023/14115.
Testo completoAbstract (sommario):
This thesis contributes to the literature on the choice of transport mode for commuting trips, with special focus on the difference between urban and rural commuting in Scotland. The thesis begins by giving an overview of discrete choice theory and some empirical models consistent with this theory, before reviewing the literature on empirical applications of mode choice models for commuting trips. In the following, multinomial, nested and mixed logit models using data from a survey of commuters in the University of St Andrews are developed. The models are used to estimate aggregate mode-choice elasticities that can assist the development of efficient car reduction policies in St Andrews and other small towns in rural areas. The direct elasticities of the car mode are found to be comparable to estimates reported in studies of urban commuting, while the demand for public transport is found to be considerably more elastic. The value of in-vehicle travel time is found to be lower than in most studies of urban commuting, reflecting that the roads in the St Andrews area are relatively uncongested. Subsequently, current car drivers' willingness to use a Park and Ride service prior to the implementation of such a service are examined. The results show that the modal shift away from parking on-site will be small unless the new service is accompanied by measures aimed at making parking on-site less attractive such as introducing parking charges. Finally, the effect of the 'compact city' on modal split and congestion are examined. As well as making urban transport more sustainable as a result of an increase in the use of public transport, making cities more compact is found to contribute to lower levels of congestion in urban areas through a reduction in complex trip chains.
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Beville, S. T. "Modelling differences in angler choice behaviour with advanced discrete choice models". Lincoln University, 2009. http://hdl.handle.net/10182/2332.
Testo completoAbstract (sommario):
New Zealand is internationally renowned for having some of the finest and most challenging trout fishing in the world. However, due to continuing development and angling pressure many fishing sites are showing signs of environmental degradation and over fishing. This trend is almost certain to continue into the future given continued population and economic growth. Understanding the determinants of site choice, preference heterogeneity and anglers’ substitution patterns is fundamentally important to fishery managers who have the difficult task of maintaining quality angling experiences on a number of fishing sites, managing angling pressure and maintaining license sales. Recent advances in simulation techniques and computational power have improved the capability of discrete choice models to reveal preference heterogeneity and complex substitution patterns among individuals. This thesis applies and evaluates a number of state-of-the-art discrete choice models to study angler site choice in New Zealand. Recreation specialisation theory is integrated into the analysis to enhance the behavioural representation of the statistical models. A suite of models is presented throughout the empirical portion of this thesis. These models demonstrate different ways and degrees of explaining preference heterogeneity as well as identifying anglers’ substitution patterns. The results show that North Canterbury anglers’ preferences vary considerably. Resource disturbances such as riparian margin erosion, reduced water visibility and declines in catch rates can cause significant declines in angler use of affected sites, and at the same time non-proportional increases in the use of unaffected sites. Recreation specialisation is found to be closely related to the types of fishing site conditions, experiences and regulations preferred by anglers. Anglers’ preference intensities for fishing site attributes, such as catch rates, vary across different types of fishing sites. This location specific preference heterogeneity is found to be related to specialisation. Overall, the empirical findings indicate that conventional approaches to modelling angler site choice which do not incorporate a strong understanding of angler preference heterogeneity can lead to poorly representative models and suboptimal management and policy outcomes.
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Hunt, John Douglas. "Modelling commuter parking location choice and its influence on mode choice". Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.237902.
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Lee, Rabinder. "Aspects of affective action choice : computational modelling". Thesis, Imperial College London, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.542964.
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Rutledge, M. P. "Assessing demand for organic lamb using choice modelling". Diss., Lincoln University, 2009. http://hdl.handle.net/10182/1110.
Testo completoAbstract (sommario):
The worldwide market for organic foods is growing fast, but New Zealand meat producers have been slow to respond. Specifically, New Zealand producers have little or no organic lamb products for export or domestic sale. Part of the reason for this hesitancy to meet demand with supply is that the nature of the demand and consumer willingness to pay for the product is not well understood. The purpose of this study is to investigate New Zealand organic food consumers’ attitudes towards organic food and production methods and to evaluate consumer willingness to pay for an organic lamb product. Data for this study was collected using computer aided personal interviewing (CAPI) in supermarkets and speciality stores in Christchurch and Wellington. The study questioned consumers about their consumption habits, attitudes towards organic food and production methods and presented choice modelling scenarios to test willingness to pay for different attributes of lamb. Factor analysis is used to group the 12 attitudinal questions into three factors which were then placed into a two step cluster analysis to create consumer segments. Choice modelling was then used to measure consumer preferences for the tested attributes of lamb. From the factor and cluster analysis three distinct consumer segments were found and labelled as Committed Organic Seekers, Convenience Organic Consumers and Incidental Organic Consumers. These labels reflect each group’s organic consumption habits and attitudes towards organic food. The choice modelling results show that there is a willingness to pay for organic lamb. The three identified consumer groups state they would pay a premium of 61%, 44% and 26% respectively for organic lamb over standard pasture raised lamb. This paper gives an insight into consumer attitudes and preferences towards a product that could provide a way for New Zealand farmers to increase their returns. It contributes to the body of knowledge about the likely consumer profiles of regular consumers of organic food. There are only a few other studies that have attempted to measure consumer attitudes and willingness to pay for organic meat, however, the author is not aware of any published example of a study that has specifically investigated demand for organic lamb anywhere in the world. The study provides information about stated willingness to pay for five different attributes of lamb; this information should be of value in assisting the industry by showing which product offerings are likely to generate the highest sale price.
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Tazzyman, S. J. "Modelling the evolution and consequences of mate choice". Thesis, University College London (University of London), 2010. http://discovery.ucl.ac.uk/814889/.
Testo completoAbstract (sommario):
This thesis considers the evolution and the consequences of mate choice across a variety of taxa, using game theoretic, population genetic, and quantitative genetic modelling techniques. Part I is about the evolution of mate choice. In chapter 2, a population genetic model shows that mate choice is even beneficial in self-fertilising species such as Saccharomyces yeast. In chapter 3, a game theoretic model shows that female choice will be strongly dependent upon whether the benefits are fixed, so that females receive the same fitness boost from a mating with a given male regardless of how many matings that male has, or dilutable, where the more females a male mates with, the lower the expected benefit to each. This leads to the prediction that mating skew should be higher in species in which the benefits of mate choice are hypothesised to be due to good genes. Part II is about the consequences of mate choice. The theoretical prediction from chapter 3 is borne out by a literature review of studies of wild populations of birds in chapter 4. In chapter 5, a quantitative genetic model about poison-dart frogs suggests that sexual selection can speed up the effect of random genetic drift. This may be of more general importance, further widening the evolutionary impact of sexual selection. Finally, in chapter 6, a game theoretic model of sperm competition shows that pre-copulatory mate choice can also have evolutionary effects upon post-copulatory behaviour, affecting the optimal ejaculate expenditure of males. Overall, mate choice is shown to be an important evolutionary force, with wide-ranging ramifications across diverse taxa, and eects so varied as to include the evolution of sex, the genetic variation in species, speciation, and post-copulatory behaviour, amongst others. These effects can be effectively explored using mathematical modelling.
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Arabikhan, Farzad. "Telecommuting choice modelling using fuzzy rule based networks". Thesis, University of Portsmouth, 2017. https://researchportal.port.ac.uk/portal/en/theses/telecommuting-choice-modelling-using-fuzzy-rule-based-networks(b088b779-8daa-441e-b0a0-7c9641e1f08b).html.
Testo completoAbstract (sommario):
Telecommuting as an approach in transportation demand management has made the news a lot in recent years. Technology has enabled this growing trend, and more and more companies and families are taking advantages of it. Adopting telecommuting is a multidimensional decision making process that involves different aspects of life such as family, work and many more. Modelling telecommuting enables employers and employees to understand the main factors that influence on decision making about adopting telecommuting. The role of subjective knowledge and linguistic variables cannot be ignored in human decision making process and Fuzzy Logic has proved to be a powerful tool for knowledge-based decision-making systems. Telecommuting as a multifaceted decision involves more on subjective knowledge rather that accurate numbers. Thus, fuzzy logic is applied for modelling telecommuting. Moreover, the complex internal decision making process for adopting telecommuting reveals the role of various factors at different levels that influence on the outcome of the decision. Therefore, Fuzzy Rule Based Network, as a novel approach in modelling complex systems, is utilised. Using Fuzzy Network as a transparent approach, enables to understand the role of external inputs, intermediate variables and their interaction in modelling telecommuting. According to choice theory and in order to find the maximum utilities of alternatives in telecommuting, the Fuzzy Network is tuned and optimised in terms of rules and membership function using Genetic Algorithm and Fuzzy c-mean clustering method. In addition, to reduce the size of Fuzzy Network, an input and branch selection method is proposed. Linguistic composition of the nodes in Fuzzy Network is also performed by an efficient method to reduce computational costs. Results highlight the most important external and intermediate variables as well as decision rules in describing the suitability of telecommuting. Also, a Multinomial Logit model, as benchmark model, is developed to compare models performances which shows the superiority of the proposed method in transparency, efficiency and interpretability criteria. The main contributions of this research can be highlighted in modelling the suitability of telecommuting using Fuzzy Rule Based Network, developing fuzzy utility model using Fuzzy Rule Based Network, tuning Fuzzy Rule Based Network using Genetic Algorithm, input and branch selection for Fuzzy Rule Based Network and finally proposing an efficient method for linguistic composition of Rule Based Network.
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Bowen, Neil Evan. "Modelling choice in digital writing : functional revisions and 'texture'". Thesis, Cardiff University, 2016. http://orca.cf.ac.uk/97609/.
Testo completoAbstract (sommario):
In this thesis, the digital writing practices of two 2nd year undergraduates are examined in terms of the functions and structures of their revision activity. Using systemic functional linguistics as an underlying framework, the project takes a first step toward to a dynamic description of written text in functional terms. To date, research into dynamic descriptions of language (i.e. the logogenesis, or unfolding of meaning in a text) has been almost entirely based upon data related to the spoken mode. Furthermore, research into revision activity has tended to ignore the functionality or meaning inherent in such revisions. The existing research has, instead, primarily focused on cognitive processes (for e.g., pause times) or which language structures, such as parts of speech, are more frequently involved in revisions that others. Ultimately, this thesis works toward providing a dynamic description of the language functions and revisions involved in revision activity in two student writers. To do this, it makes use of software called keystroke logging to record how two writers compose four academic essays on their computers. Such technology allows us to model the unfolding of a written text in much the same way as a tape recording allows researchers to model the unfolding of a speech. By examining how these writers revise text in light of academic expectations (a 'valued' configuration of field, tenor, and mode register variables present in language choices) and digital mediation (computer afforded composing practices), the thesis shows how certain language functions and structures may play a key role when it comes to shaping an academic essay. In this light, this thesis takes a first step to providing a dynamic description of what is usually analysed solely in synoptic terms, by showing how we can analyse written text as process (an evolving entity) rather than just a product (a static entity). Because of this, a new model of analysis – a combination of keystroke data and functional systemics – is proposed, which can provide an additional perspective to the already existing methods of examining writer behaviour by looking at meaning making practices in revision activity.
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Habib, Pathan Agha Faisal. "Modelling travellers' choice of information sources and of mode". Thesis, University of Leeds, 2010. http://etheses.whiterose.ac.uk/3884/.
Testo completoAbstract (sommario):
This study investigates the travellers' choice of information sources and their subsequent mode choice decisions. The goal of this study is to develop a comprehensive choice model that can capture the information acquisition process by predicting the choice of information sources together with its effects on modal choices of the travellers. A decision making framework for travel information acquisition is developed and the abstract terms, necessary to be tested in the models, are identified. A Stated Preference experiment is developed based on the complicated decision making process and an interactive CATI questionnaire is designed to cope with it. Utility functions are formulated by expanding travellers' choice set to include different combinations of the viable sources of information and with the inclusion of policy sensitive variables. The research employs a wide range of modelling methodologies and examines a range of traditional and newly developed calibration and estimation procedures including Mixed Logit models with individual specific parameters and the newly developed Random Regret Minimisation framework. The study also analyses the effects of travel planning websites on travel decisions and establishes a link between content, design, advertisements, and presentation of information on overall modal shift. The results indicate that travellers give credence to government owned sources and give more importance to their own previous experiences followed by multimodal websites, train websites, friends and coach websites respectively. A website with less search time, specific infonnation on users' own criteria, and real time information is regarded as most attractive by the travellers. The study also found that the market share of the modes increases when information sources show decreased travel time and cost values and the maximum results are achieved when different information sources give the same information to the travellers. These results show that information sources could be used to influence the mode choice of the travellers.
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John, Paul. "Modelling Recreation Demand Using Choice Experiments : Using Swedish Snowmobilers Demand for Groomed trails". Thesis, Högskolan Dalarna, Nationalekonomi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:du-4642.
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This paper is concerned with the use of the choice experiment method for modeling the demand for snowmobiling . The Choice Experiment includes five attributes, standard, composition, length, price day card and experience along trail. The paper estimates the snowmobile owners’ preferences and the most preferred attributes, including their will-ingness to pay for a daytrip on groomed snowmobile trail. The data consists of the an-swers from 479 registered snowmobile owners, who answered two hypothetical choice questions each. Estimating using the multinominal logit model, it is found that snow-mobilers on average are willing to pay 22.5 SEK for one day of snowmobiling on a trail with quality described as skidded every 14th day. Furthermore, it is found that the WTP increases with the quality of trail grooming. The result of this paper can be used as a yardstick for snowmobile clubs wanting to develop their trail net worth, organizations and companies developing snowmobiling as a recreational activities and marketers in-terested in marketing snowmobiling as recreational activities.
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Marais, Andre Louis. "Developing an alternative approach to mode choice modelling with the application of modelling Gautrain patronage". Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86475.
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Thesis (MScEng)--Stellenbosch University, 2014.ENGLISH ABSTRACT: Mode choice modelling is an important and versatile tool that can aid decision makers with transit related strategies and scenario planning. The traditional approach to modelling public transport is labour intensive and requires many resources. The expensive nature of developing mode choice models can also act as a deterrent for developing a model. Not having access to a functional mode choice model can force decision makers to make important decisions without having access to proper information. There is therefore a need to provide a simplified solution for developing a functional mode choice model that can be developed and maintained with fewer resources. This research project explores the possibility of developing a simplified alternative approach to public transport modelling that can model mode choice behaviour with the same degree of accuracy as traditional models. The modelling steps employed in this research project were the typical four step demand modelling approach, but the principles employed differ slightly. The focus area of this research project is the development of simplified utility functions and the calibration thereof. Typical mode choice models coincide with many assumptions, variations and uncertainties. In this research project the proposed utility functions are simplified by incorporating most of the assumptions and intangible components of the utility function into a single station to station specific calibration factor. The hypothesis is that a simplified alternative approach to the utility functions can still provide a model that is purpose built and functional. The application of the proposed mode choice model is to model the mode choice between the Gautrain and private vehicles as the major mode of transport.
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Shen, Yu. "Car fleet modelling : Data processing and discrete choice model estimation". Thesis, KTH, Transportvetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-43719.
Testo completoAbstract (sommario):
This thesis deals with the modelling of the choice of new car based on the registration data of the whole Sweden car fleet for 2005 to 2010. It is divided into two parts. In the first part, to obtain the observations of new car choices for the discrete choice modelling, a subset based on the first registration date of each car is extracted. Then, a descriptive analysis based on the new car choice data is presented to find the variances of the attributes for the modelling. Specifically, two major issues are paid attention to. One is the change of market share of each car make in these years and the other is the incremental demand of diesel and hybrid fuel cars. The second part of the thesis deals with the discrete choice modelling. In order to designate the alternatives, another dataset showing the new car supply in Sweden is introduced. In the supply data, the alternatives are shown in the car version level, whereas the registration data only contain the names of car models. Additionally, the supply data also have some attributes that are unavailable in the registration, e.g. price. Thus, this thesis presents various matching methods to match the supply and the registration to define the alternatives for the modelling and also to obtain a higher precision of each attribute than that in matching with model names only. Finally, we choose to match the data by the same model name with the same maximum power, which is defined as the “model-engine” level. Therefore, based on these model-engine level alternatives, 18 MNL models are estimated from 2005 to 2010, with 3 different ownerships, namely private owned, company owned and company owned but leasing to its employee which is named as “leasing users”. The results show the slump of the brand constants of Saab among these years in private owners and leasing users due to the close-down crisis when the coefficient of Volvo is fixed to zero. By contrast, the brand value of Kia for private owners and the value of VW for leasing users go up. Meanwhile, this thesis analyses a shift of car buyers’ attitude to the alternative fuel car from negative in 2006 to positive in 2007 when a “clean car” compensation policy is implemented from Jan. 2007 to Jul. 2009. And in 2010, the coefficient of the alternative fuel remains positive. These results indicate that this policy was quite successful.
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Fowell, Susan Patricia. "The performance modelling of preferential choice : a knowledge engineering approach". Thesis, Leeds Beckett University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335892.
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Rosa, Andrea. "Probit based methods in traffic assignment and discrete choice modelling". Thesis, Edinburgh Napier University, 2003. http://researchrepository.napier.ac.uk/Output/4168.
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Lee, Peter. "Three essays on modelling household labour supply". Thesis, The University of Sydney, 2013. http://hdl.handle.net/2123/12325.
Testo completoAbstract (sommario):
Labour supply modelling is one of the most prevalent research topics in the economic literature, and the employment implications are among the most persistent characteristics of public policy evaluation. This dissertation examines the employment responses of Australian households by developing economic models believed to better capture the employment behaviour of three important demographic subgroups, namely, partnered parents (married or de facto), single mothers and unemployed individuals. For each subgroup, a substantive empirical analysis is developed with the key focus on evaluating their employment responses to wage, childcare costs and public transfers. The results are of particular interest to policy makers who wish to evaluate the effects of a number of policies on household employment decisions. The first analysis examines the implications of childcare utilisation on employment behaviour of partnered parents. For mothers during the childcare phase, there is widespread consensus that childcare plays a crucial role in facilitating the transition into employment. To capture household childcare implications, this analysis proposes a behavioural labour supply model where labour force participation, hours worked and the provision of parental care are endogenous. The model establishes relationships between optimal time spent in parental care and work by incorporating structural time constraints of parents and children within the household, while it is sufficiently flexible to characterise a large variety of household responses. The model for partnered parents is employed to estimate the effects of wage and the price of childcare on employment and parenting behaviour and well-being, using a cross-sectional dataset formed by pooling three waves of Household, Income and Labour Dynamics in Australia (HILDA) data from 2009 to 2011. The analysis reports wage elasticity and childcare price elasticity for the sample and subgroups within the sample. Using behavioural simulation techniques, the analysis further investigates four alternative payment schemes of the Child Care Rebate (CCR) program that are less costly to implement, and their employment implications on partnered parents. These simulations have illustrated the effectiveness of childcare subsidies in shaping the willingness to supply labour among parents with children. The results suggest that childcare subsidies can be an effective means to promote female labour supply if public transfers target more responsive subgroups, such as low-income households, through the use of income means tests. The second analysis investigates the sensitivity of single mothers’ labour supply to income support programs and tax rules. A structural static model of labour supply is formulated to explicitly take into account childcare decisions. The model is applied to estimate the labour supply and the provision of parental care for Australian single mothers, where a panel dataset is constructed based on five waves of HILDA from 2006 to 2010. The time structure of the panel data requires the development of an econometric specification that is compatible with the nature of panel data. The results indicate that childcare expenses significantly undermine labour-market activities of single mothers but the effect is small for the average worker. The effect is large, however, for individuals at the bottom end of income distribution. Resulting from the adjustments of a number of budget set components, this analysis further simulates the sensitivity of parents’ labour supply to individual income support programs and tax rules. The third analysis relaxes the conventional market clearing assumption and considers labour supply decisions in a rationed labour market in which some individuals are unable to obtain work. Specifically, the probability of being unemployed is separately identified to distinguish between the inability to obtain work and not being in the labour force. A decision process similar to the double-hurdle model is incorporated in the discrete choice labour supply model, in which market participants are confronted with the risk of being unemployed. The econometric specification assumes that each individual chooses from amongst a set of discrete hour choices to maximise a predefined utility function, in which the expected utility from market participation is weighted by probability of being in employment. Within the single structural labour supply model, the household unemployment risk, preferences for consumption and leisure and the fixed costs of work are jointly estimated. The dataset is based on three waves of HILDA data between 2009 and 2011 and consists of partnered households aged between 25 and 59. The estimation results obtained from the extended model are compared to those from the conventional discrete choice model. The effects of controlling for the unemployment risk are assessed by discussing the discrepancies in the estimation results. Furthermore, this analysis investigates the sensitivity of household labour supply to program parameters, in particular, the benefits available to unemployed individuals, by simulating employment responses of hypothetical adjustments to unemployment benefits in Australia. In particular, the estimation results are applied to simulate the employment effects of two alternative payment schemes of Newstart Allowance. The results suggest that an absolute increase in the Newstart Allowance payment is likely to discourage the labour supply of working females while promoting non-working females to participate in the labour market; and a reduction in the Newstart taper rate leads to positive employment effects in both hours worked and participation. However, the impact of the Newstart Allowance benefits on male labour supply is found to be largely insignificant.
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Fry, Timothy Richard Leighton. "On the use of some Burr family distributions in econometrics". Thesis, University of Manchester, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328288.
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Agerberg, Frida. "Data interpolation for groundwater modelling : How choice of interpolation method and sample size affect the modelling results". Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-79577.
Testo completoAbstract (sommario):
Over the past several decades, the use of groundwater modelling has been increasing in order to better evaluate the complexities inherent in hydrogeological calculations. Information required for groundwater modelling is for example elevation of soil and bedrock layers, which often is collected by drilling. This is both time consuming and expensive, making it impossible to collect an unlimited number of data points. It is not uncommon that smaller hydrogeological investigations are based on only three or four sample points. To approximate values of unknown points in the study area, the known values of the measured data is interpolated. The interpolation can be done with different methods, and the estimations of the elevation of geological layers at the unknown points might vary with different methods. How the uncertainty of the interpolations then affects the modelling results is generally unknown when simulating groundwater flow. The aim of the thesis work is to investigate how hydrogeological results from groundwater models are affected by choice of interpolation method and by sample size of which the interpolation is based on. The hydrogeological models were simulated within the framework of a Swedish railway project where an unusually large number of probing data was available. The study focuses on two-dimensional, steady-state groundwater flow modelled in the software SEEP/W. Consequently, the objective of the modelling work was to simulate groundwater flow where the difference between the models was how the geometry of the geological layers was defined. The definition of the geometry was done with interpolations of the probing data with different interpolation methods and with interpolation based on different sample sizes. Twelve different interpolation methods in the software Surfer was used to interpolate the total of 357 data points. The interpolations that were estimated to be reliable were then used in the groundwater modelling. Groundwater models were also simulated based on a reduced amount of data in order to investigate the importance of sample size. The total amount of data points was reduced to 50%, 25%, 5% and 1% of the initial sample size before it was interpolated and then used to define the geometry in the groundwater models. The study showed that although the choice of interpolation method and sample size affected the results of the modelled groundwater flow rate, none of the deviations between the model results were larger than what would be considered as acceptable in a hydrogeological context. The models based on at least 90 data points showed good precision while the precision of modelled groundwater flow decreased when sample size decreased. Thus, when interpolating data for groundwater modelling, the sample size should be determined by the required precision of the study. For the modelling of the 1% data, only one of the six models was possible to simulate. This since at least three data points are required for each geological layer in order to perform interpolations, and this was only obtained in one of six randomly selected data sets. The study indicates that around 10-20 sample points is a minimum for a study area with similar conditions as the reference project in order to have a high probability of obtaining enough data of all geological layers of interest. Finally, the study indicates that there are other parameters in groundwater modelling, for example hydraulic conductivity and boundary conditions, that might have an equal of higher impact on the model results. These parameters should therefore also be determined with a high precision in order to gain accurate modelling results.Under de senaste årtiondena har användandet av grundvattenmodeller ökat för att bättre kunna hantera komplexitet inom hydrogeologiska beräkningar. För att kunna skapa en grundvattenmodell krävs exempelvis data över hur lager av jord och berg är beläget. Dessa geologiska data samlas vanligen i borrpunkter, vilket är både tidskrävande och dyrt. Detta gör det omöjligt att erhålla ett obegränsat antal mätpunkter och det är vanligt att mindre hydrogeologiska undersökningar endast utgår ifrån tre till fyra mätpunkter. Utifrån det begränsade antalet mätpunkter interpoleras kända nivåer av jord- och berglager för att approximera nivåer i okända punkter. Interpolering görs med hjälp av olika matematiska metoder och resultatet av dessa kan variera mellan olika metoder. Hur osäkerheter i interpolering sedan påverkar resultat från grundvattenmodellering är vanligtvis okänt. Syftet med examensarbetet är att undersöka hur hydrogeologiska resultat från grundvattenmodeller påverkas av val av interpolerings metod samt av antal mätpunkter som interpoleringen är baserad på. Grundvattenmodellerna skapades inom ramen av ett svenskt järnvägsprojekt där ovanligt stora mängder sonderingsdata fanns tillgängligt. Undersökningen fokuserar på steady-state grundvattenflöden i två dimensioner, modellerat i programmet SEEP/W. Undersökningen utgick därmed från sonderingsdata i referensprojektet för att skapa ett antal grundvattenmodeller, där skillnaden mellan dessa var hur nivån av de geologiska lagren definierades. Detta gjordes med hjälp av olika interpoleringsmetoder och med interpolering baserad på olika mängder data punkter. Tolv olika interpoleringsmetoder i programmet Surfer användes för att interpolera de totalt 357 data punkterna. De interpoleringar som kunde antas vara rimliga användes sedan för att definiera geometrin i olika grundvattenmodeller. Grundvattenmodeller skapades även utifrån en reducerad mängd data för att undersöka betydelsen av antal mätpunkter vid interpolering. Antal mätpunkter reducerades till 50%, 25%, 5% och 1% och interpolering av dessa användes sedan för att definiera geometrin i olika grundvattenmodeller. Studien visade att även om modeller baserade på olika interpoleringsmetoder och interpolering av olika antal mätpunkter genererade något olika resultat med avseende på modellerat grundvattenflöde, så var inget av resultaten mer avvikande än vad som i ett hydrogeologiskt sammanhang skulle klassas som acceptabelt. Vidare visade resultaten att modeller baserade på 90 data punkter eller mer hade en bra precision av modellerat grundvattenflöde samt att minskat antal mätpunkter ledde till minskad precision. Antal mätpunkter i en undersökning bör därmed väljas utifrån hur bra precision som bör uppnås. Dock kan ett lägre antal mätpunkter försvaras om erhållen precision vägs mot hur resurskrävande insamling av data är. Modelleringen av 1% data visade att endast en av de sex modellerna gick att skapa. Detta var på grund av att minst tre datapunkter för varje geologiskt lager krävdes för att interpolera data och detta uppnåddes alltså bara i en av de slumpade data seten. För att ha en hög sannolikhet att erhålla tillräckligt med data för varje jord- eller berglager av intresse indikerar denna studien på att 10 till 20 mätpunkter är tillräckligt i en undersökning med liknande förutsättningar som i referensprojektet. Slutligen så indikerar studien på att det finns andra parametrar, exempelvis hydraulisk konduktivitet och randvillkor, som kan ha liknande eller större inverkan på modellerat grundvattenflöde och för att få noggranna resultat bör även dessa parametrar bestämmas med hög precision.
22
Gardner, Benjamin David. "What drives car use? : modelling psychological antecedents of travel mode choice". Thesis, University of Sussex, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.444119.
Testo completo
23
Jordan, René Janelle. "Agent-based modelling of housing choice in the EASEL regeneration district". Thesis, University of Leeds, 2011. http://etheses.whiterose.ac.uk/2023/.
Testo completoAbstract (sommario):
Housing choice behaviour is made up of a wide array of dynamic individual level behaviour which can be recreated and explored using agent-based modelling (ABM). In the UK, there has been a renewed focus on urban regeneration policies over the past decade by the national government. Such policies seek to deal with the problems of deprivation in communities segregated by socioeconomic status. Using the case study district of East and South Easel Leeds (EASEL), an area known to have pockets of disadvantaged communities, the impacts of regeneration policy will be explored. A computer simulation of residential mobility and regeneration policy is created, in this way, the potential outcomes of regeneration schemes are explored.
24
Chen, Chunmei. "Modelling Train Station Choice under Uncertainty for Park and Ride Users". Thesis, Curtin University, 2019. http://hdl.handle.net/20.500.11937/76066.
Testo completoAbstract (sommario):
This research develops a novel theoretical framework for modelling train station choice under uncertainty for park and ride users. Three uncertain factors, travel time to station, parking search time and crowding on trains, are modelled to estimate station choice probabilities, the risk attitudes of respondents and the preference heterogeneity of individuals. This study may support planning decisions on the location, price and capacity of P&R facilities, and provide evidence for evaluating P&R investment decisions.
25
Khan, Omer Ahmed. "Modelling passenger mode choice behaviour using computer aided stated preference data". Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/16500/1/Omer_Khan_Thesis.pdf.
Testo completoAbstract (sommario):
Redland Shire Council (RSC) has recently completed the preparation of Integrated Local Transport Plan (ILTP) and started its implementation and monitoring program. One of the major thrusts of the ILTP is to reduce the car dependency in the Shire and increase the shares of sustainable environmental-friendly travelling modes, such as walking, cycling and public transport.
To achieve these objectives, a mathematical model is needed that is capable of modelling and forecasting the travelling mode choice behaviour in the multi modal environment of Redland Shire. Further, the model can be employed in testing the elasticity of various level-of-service attributes, under a virtual travel environment, as proposed in the ILTP, and estimating the demand for the new travelling alternatives to private car, namely the bus on busway, walking on walkway and cycling on cycleway.
The research estimated various nested logit models for different trip lengths and trip purposes, using the data from a stated preference (SP) survey conducted in the Shire. A unique computer assisted personal interviewing (CAPI) instrument was designed, using both the motorised (bus on busway) and non-motorised travelling modes (walking on walkway and cycling on cycleway) in the SP choice set. Additionally, a unique set of access modes for bus on busway was also generated, containing hypothetical modes, such as secure park and ride facilities and kiss and ride drop-off zones at the busway stations, walkway and cycleway facilities to access the busway stations and a frequent and integrated feeder bus network within the Shire. Hence, this study created a totally new virtual travel environment for the population of Redland Shire, in order to record their perceived observations under these scenarios and develop the mode choice models.
From the final model estimation results, it was found that the travel behaviour forecasted for regional trip-makers is considerably different from that of local trip-makers. The regional travellers for work, for instance, were found not to perceive the non-motorised modes as valid alternatives to car, possibly due to longer trip lengths. The value of time (VoT) determined for local work trip-makers (16.50 A$/hr) was also found to be higher than that of regional work trip-makers (11.70 A$/hr).
From the survey analysis, a big part of the targeted population was found to be car captives, who are not likely to switch from cars to public transport; even if a more efficient transit infrastructure is implemented. In the past, the models have been generally calibrated using the mode choice survey data only, while that of the captive users were ignored. This yields a knowledge gap in capturing the complete travel behaviour of a region, since the question of what particular biases can be involved with each model estimation parameter by the captives remain unresolved. In this research, various statistical analyses were performed on the car captive users' data by categorising them into various trip characteristics and household parameters, in order to infer the relative influence of the car captive population on the travel behaviour of the study area.
The outcomes of the research can assist the policy makers in solving the strategic issues of transit planning, including the future development of a busway corridor, with an efficient transit access mode network. The research findings can also be utilised in evaluating the feasibility of developing walkways and cycleways in the Shire, along with appraising the relative influence of car captive users on the travel behaviour forecasts for the study area.
26
Khan, Omer Ahmed. "Modelling passenger mode choice behaviour using computer aided stated preference data". Queensland University of Technology, 2007. http://eprints.qut.edu.au/16500/.
Testo completoAbstract (sommario):
Redland Shire Council (RSC) has recently completed the preparation of Integrated Local Transport Plan (ILTP) and started its implementation and monitoring program. One of the major thrusts of the ILTP is to reduce the car dependency in the Shire and increase the shares of sustainable environmental-friendly travelling modes, such as walking, cycling and public transport. To achieve these objectives, a mathematical model is needed that is capable of modelling and forecasting the travelling mode choice behaviour in the multi modal environment of Redland Shire. Further, the model can be employed in testing the elasticity of various level-of-service attributes, under a virtual travel environment, as proposed in the ILTP, and estimating the demand for the new travelling alternatives to private car, namely the bus on busway, walking on walkway and cycling on cycleway. The research estimated various nested logit models for different trip lengths and trip purposes, using the data from a stated preference (SP) survey conducted in the Shire. A unique computer assisted personal interviewing (CAPI) instrument was designed, using both the motorised (bus on busway) and non-motorised travelling modes (walking on walkway and cycling on cycleway) in the SP choice set. Additionally, a unique set of access modes for bus on busway was also generated, containing hypothetical modes, such as secure park and ride facilities and kiss and ride drop-off zones at the busway stations, walkway and cycleway facilities to access the busway stations and a frequent and integrated feeder bus network within the Shire. Hence, this study created a totally new virtual travel environment for the population of Redland Shire, in order to record their perceived observations under these scenarios and develop the mode choice models. From the final model estimation results, it was found that the travel behaviour forecasted for regional trip-makers is considerably different from that of local trip-makers. The regional travellers for work, for instance, were found not to perceive the non-motorised modes as valid alternatives to car, possibly due to longer trip lengths. The value of time (VoT) determined for local work trip-makers (16.50 A$/hr) was also found to be higher than that of regional work trip-makers (11.70 A$/hr). From the survey analysis, a big part of the targeted population was found to be car captives, who are not likely to switch from cars to public transport; even if a more efficient transit infrastructure is implemented. In the past, the models have been generally calibrated using the mode choice survey data only, while that of the captive users were ignored. This yields a knowledge gap in capturing the complete travel behaviour of a region, since the question of what particular biases can be involved with each model estimation parameter by the captives remain unresolved. In this research, various statistical analyses were performed on the car captive users' data by categorising them into various trip characteristics and household parameters, in order to infer the relative influence of the car captive population on the travel behaviour of the study area. The outcomes of the research can assist the policy makers in solving the strategic issues of transit planning, including the future development of a busway corridor, with an efficient transit access mode network. The research findings can also be utilised in evaluating the feasibility of developing walkways and cycleways in the Shire, along with appraising the relative influence of car captive users on the travel behaviour forecasts for the study area.
27
Loo, Sara Li-Yen. "Mathematical Modelling of the Evolution of Human Behaviours and Strategic Choice". Thesis, The University of Sydney, 2019. http://hdl.handle.net/2123/20210.
Testo completoAbstract (sommario):
Evolutionary anthropology seeks answers to the eternal philosophical question: how have we come to be? Studies in evolutionary anthropology attempt to explain the evolution of uniquely human behaviours by investigating the mechanisms that drive different trajectories. In this thesis dynamic mathematical models are built to investigate the tradeoffs defining divergent evolutionary pathways of strategic choice. This is done by comparing evolutionary equilibria at great ape-like and hunter-gatherer-like life histories. One investigation considers the evolution of pair bonding in humans. Mate guarding that pays off in increased likelihood of obtaining paternities outperforms strategies of paternal care at hunter-gatherer-like male-biased sex ratios while multiple mating is the evolutionary equilibrium at chimpanzee-like female-biased sex ratios. This demonstrates the promise of mate guarding as a pathway to social monogamy and links male reproductive strategies to the grandmother hypothesis through sex ratio dependence. Competition and care as male reproductive strategies are then investigated more generally in an ordinary differential equation model. Equilibria depend on life history and benefit parameters. An integro-difference equation model that explores the effect of non-parental imitation on the coevolution of low fertility at high socio-economic status is also given, applying Darwinian selection to a contemporary case of cultural evolution. This thesis shows that competitive strategies often pay off at human-like parameters despite the possibility of increased offspring survivorship through care. However, coexistence or persistence of a non-competitive strategy may also occur under specific parameters. Uncovering drivers of the evolution of different male reproductive strategies is important for guiding further research and shedding light on why we are so different from other great apes.
28
Fennell, Alex. "Does Response Modality Influence Conflict? Modelling Vocal and Manual Response Stroop Interference". The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1490611523266134.
Testo completo
29
Börjesson, Maria. "Issues in Urban Travel Demand Modelling : ICT Implications and Trip timing choice". Doctoral thesis, KTH, Transporter och samhällsekonomi, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4092.
Testo completoAbstract (sommario):
Travel demand forecasting is essential for many decisions, such as infrastructure investments and policy measures. Traditionally travel demand modelling has considered trip frequency, mode, destination and route choice. This thesis considers two other choice dimensions, hypothesised to have implications for travel demand forecasting. The first part investigates how the increased possibilities to overcome space that ICT (information and communication technology) provides, can be integrated in travel demand forecasting models. We find that possibilities of modelling substitution effects are limited, irrespective of data source and modelling approach. Telecommuting explains, however, a very small part of variation in work trip frequency. It is therefore not urgent to include effects from telecommuting in travel demand forecasting. The results indicate that telecommuting is a privilege for certain groups of employees, and we therefore expect that negative attitudes from management, job suitability and lack of equipment are important obstacles. We find also that company benefits can be obtained from telecommuting. No evidences that telecommuting gives rise to urban sprawl is, however, found. Hence, there is ground for promoting telecommuting from a societal, individual and company perspective. The second part develops a departure time choice model in a mixed logit framework. This model explains how travellers trade-off travel time, travel time variability, monetary and scheduling costs, when choosing departure time. We explicitly account for correlation in unobserved heterogeneity over repeated SP choices, which was fundamental for accurate estimation of the substitution pattern. Temporal constraints at destination are found to mainly restrict late arrival. Constraints at origin mainly restrict early departure. Sensitivity to travel time uncertainty depends on trip type and intended arrival time. Given appropriate input data and a calibrated dynamic assignment model, the model can be applied to forecast peak-spreading effects in congested networks. Combined stated preference (SP) and revealed preference (RP) data is used, which has provided an opportunity to compare observed and stated behaviour. Such analysis has previously not been carried out and indicates that there are systematic differences in RP and SP data.QC 20100825
30
Börjesson, Maria. "Issues in urban travel demand modelling : ICT implications and trip timing choice /". Stockholm : Division for Transport and Location Analysis, Royal Institute of Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4092.
Testo completo
31
Renwick, Alan. "Complex causal modelling : institutional choice in Hungary, Czechoslovakia and Poland, 1989-1990". Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.402248.
Testo completo
32
Anastasiou, Andreas. "Modelling food demand to evaluate the effects of dietary choice on health". Thesis, University of Reading, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.501365.
Testo completoAbstract (sommario):
The influence of diet on health is widely recognised and documented. Diet is a product of choices made by consumers and as such is influenced by a variety of factors. By understanding these influences it will be possible to design policies that are cost effective in delivering improvements in diets that are of public interest. This contributes to the gap in knowledge about the pattern of food purchasing behaviour among households in the United Kingdom and its links with the increasing prevalence of diet-related diseases (e.g. obesity).
33
Takama, Takeshi. "Stochastic agent-based modelling for reality : dynamic discrete choice analysis with interaction". Thesis, University of Oxford, 2005. http://ora.ox.ac.uk/objects/uuid:07a643ed-c98a-4e66-936b-e8b558dbc1e3.
Testo completoAbstract (sommario):
This D.Phil. thesis develops a new agent-based simulation model to improve the results of analysis, which solely uses discrete choice modelling, as well as to analyse the effects of a road user charging scheme for the Upper Derwent Valley in the Peak District National Park. The advantages of discrete choice analysis are well known. However, results with these conventional conventional approaches, which conduct analysis solely with discrete choice models, can be biased if interaction and learning effects are significant. The Minority Game, in which agents try to choose the option of the minority side, is an appropriate tool to deal with these problems. The situation in the Upper Derwent Valley can be explained with economic game theories and the Minority Game. The two approaches mutually help to analyse the situation in the Upper Derwent Valley leading to the development of a stochastic Minority Game. The stochastic Minority Game was tested with an online game (questionnaire), which was played 3,886 times by response in all around the world. The practical part of this thesis examines the components of the stochastic Minority Game with the data collected around the Upper Derwent Valley. The main data was collected using a stated preference survey. Overall, 700 questionnaires were distributed and 323 of them were returned (i.e. a return rate of 46.1 %). In the practical part, the agent-based model has four sub modules: 1) Multinomial mixed logit model for mode choice, 2) Binary logit model for parking location choice, 3) Markov queue model for parking network, and 4) the Minority Game for parking congestion and learning. This simulation model produces comprehensive outputs including mode choices, congestion levels, and user utilities. The results show that the road user charging scheme reduces car demand in the Upper Derwent Valley and ensures a reduction in congestion at the parking areas. The model also shows that an exemption will increase the utilities of elderly visitors without substantially sacrificing those of younger visitors. In conclusion, the simulation model demonstrated that oversimplification in conventional approaches solely using discrete choice models gave significant biases when real world problems were analysed.
34
Silva, Ana Carina Vieira da. "Integrating public preferences in biodiversity conservation decision-making: a choice-modelling approach". Doctoral thesis, ISA-UL, 2017. http://hdl.handle.net/10400.5/14959.
Testo completoAbstract (sommario):
Doutoramento em Alterações Climáticas e Políticas de Desenvolvimento Sustentável, especialidade em Ciências do Ambiente - Universidade de Lisboa: Faculdade de Ciências, Faculdade de Letras, Instituto de Ciências Sociais, Instituto Superior de Agronomia, Instituto Superior Técnico / Universidade Nova de Lisboa: Faculdade de Ciências Sociais e Humanas, Faculdade de Ciências e TecnologiaThe need to reverse current trends of biodiversity loss is acknowledged by a wide range of international scientific and political initiatives. Along with the scientific and political agenda, the protection of biodiversity has become an important issue in public opinion too. Nevertheless, general public concerns are not typically considered by decision-makers and conservation planning continues to emphasize only ecological concerns ignoring social considerations. But since public involvement is essential for the success of conservation initiatives we must start thinking on how to capture public concerns and preferences so that they can be posteriorly integrated in conservation decision-making. This was the starting point for the present dissertation. This dissertation proposes an economic valuation approach to capture public preferences regarding biodiversity conservation and to translate them into monetary values, so they can be later incorporated in decision-making to ensure a truly societal management. Using choice experiments method allows for a valuation approach focused on biodiversity roles biodiversity plays for human well-being (benefits) rather than on components, which should simplify the cognitive process of preference formation and translation into monetary values. Considering this main aim, four main research questions arose: 1) Is the public aware of biodiversity roles/benefits? 2) Can we translate public preferences for biodiversity roles into monetary terms through economic valuation? 3) Are public preferences affected by the excludability degree of biodiversity roles? and 4) Are public preferences for biodiversity roles influenced by environmental education and a close contact with some of its components? Research results show that the general public share interesting social representations of biodiversity and seems to choose conservation priorities rationally. Additionally, choice modelling seems to be an appropriate approach to capture and translate public preferences into monetary terms allowing for biodiversity decomposing in different roles (or benefits) perceived by the public
N/A
35
Edwards, Miriam Ruth Germaine. "An application of rational choice theory to petroleum policies in Canada, Britain, and Norway". Thesis, University of Edinburgh, 1988. http://hdl.handle.net/1842/18858.
Testo completo
36
Bitzios, D. "Visitor mode choice". Thesis, Queensland University of Technology, 2001. https://eprints.qut.edu.au/36146/1/36146_Bitzios_2001.pdf.
Testo completoAbstract (sommario):
Mode choice models have, in the past, been disaggregated by a range of work and personal trip purposes. Linear expressions have been developed describing the utility
or generalised cost of each transport mode option within each trip purpose category. With improving data collection, storage and processing facilities, highly disaggregate models are finding wider application in mode choice modelling. Disaggregate mode choice models developed thus far have not explicitly defined
visitor mode choice and have therefore assumed that visitors' mode choice
characteristics are similar to those of residents. In areas such as the Gold Coast,
Australia, visitors comprise a significant proportion of the overall travelling population and are expected to have intrinsically different mode choice characteristics to those of residents. This thesis investigates the factors which affect visitor mode choice and provides
relationships between visitor mode choice and a range of trip-based and visit-based variables. These relationships are intended to be the first step in towards the
development of visitor-specific mode choice models. As such, this research is highly qualitative with some basis on survey data. The relationships developed are drawn
from the available data, however it is envisaged that further, more rigorous survey would be required to confirm the statistical validity of the relationships developed. Two separate surveys were conducted to collect data on visitor mode choice. The first survey involved a loosely-structured interview survey to develop an
understanding of visitor's mode choice thought processes as to when and why they make certain mode choice decisions. The qualitative data collected in the first
survey was used to develop a better understanding of the range of variables considered by visitors when selecting their mode(s) for use during a visit. The second
survey was an interview survey of potential ferry users within which a range of general mode choice information was gathered. The combination of the more quantitative data collected in the second survey and the more qualitative information collected in the first survey provided the basis for hypothesising the visitor mode
choice relationships in this research.
The data from both the first and second surveys was collated and analysed to determine key relationships between visitor mode choice and a range of trip-based
and visit-based considerations. Duration of the visit was found to be a key determinant of the degree of pre-planning and how fixed (captive) to particular
modes visitors were. Duration of the visit was also shown to affect mode choice elasticity for time and cost based variables, as did the availability of a car which
essentially removed all other mode choice options from visitor's considerations. Extensions of this research could include quantification of the relationships through
detailed interview surveys and the use of advanced technologies (e.g. GPS) to track visitor movements. This data would enable the development of visitor mode choice
models disaggregated by visit-type and considering visit variables such as duration of stay, degree of pre-planning, local knowledge and group size; in conjunction with trip-based variables such as frequency, price, comfort and convenience.
37
Melatos, Mark. "Modelling Regional Trade Agreements". Thesis, The University of Sydney, 2002. http://hdl.handle.net/2123/486.
Testo completoAbstract (sommario):
In the last twenty years, regional trade agreements have proliferated. These have usually taken the form of customs unions (CUs) or free trade areas (FTAs). This thesis concentrates mostly on the formation and behaviour of CUs. Union members levy a common external tariff (CET) on non-members. Existing theoretical models, however, do not agree on how the CET rate is chosen. Every model imposes a different choice rule exogenously. In this thesis, for the first time, plausible choice rules, based on the CU's social welfare function, are derived endogenously. The strategic behaviour of members and non-members, reveals that responsibility for CET choice tends to be assumed by the member that can induce the rest of the world to levy those tariffs members prefer to face. Relatively few general results exist describing the relationship between country characteristics and trade bloc formation. Here, new light is shed on this issue, by systematically analysing bloc formation in an asymmetric world, and investigating the role of preferences in coalition formation. It is found that global free trade is most likely to arise when all countries are similar. Customs unions tend to form between relatively well-endowed countries or those with similar preferences. It is also demonstrated that CUs will usually Pareto dominate FTAs, except where preferences differ significantly. The role of transfers in CU formation has received relatively little attention in the regionalism literature. In this thesis, optimal intra-union transfers are introduced and their impact on CET choice is investigated. The impact of transfers on CU behaviour depends on the direction of the transfer. When the relatively inelastic member is the recipient, the CU responds less aggressively to non-member tariff choices than it does when transfers are not permitted. However, if the relatively elastic member is the transfer recipient, the union's aggression increases. Moreover, when one union member exercises a similar degree of control over both CET and transfer choice, then the equilibrium CET tends to be lower than in the corresponding no-transfers situation.
38
Melatos, Mark. "Modelling Regional Trade Agreements". University of Sydney. Economics and Political Science, 2002. http://hdl.handle.net/2123/486.
Testo completoAbstract (sommario):
In the last twenty years, regional trade agreements have proliferated. These have usually taken the form of customs unions (CUs) or free trade areas (FTAs). This thesis concentrates mostly on the formation and behaviour of CUs. Union members levy a common external tariff (CET) on non-members. Existing theoretical models, however, do not agree on how the CET rate is chosen. Every model imposes a different choice rule exogenously. In this thesis, for the first time, plausible choice rules, based on the CU's social welfare function, are derived endogenously. The strategic behaviour of members and non-members, reveals that responsibility for CET choice tends to be assumed by the member that can induce the rest of the world to levy those tariffs members prefer to face. Relatively few general results exist describing the relationship between country characteristics and trade bloc formation. Here, new light is shed on this issue, by systematically analysing bloc formation in an asymmetric world, and investigating the role of preferences in coalition formation. It is found that global free trade is most likely to arise when all countries are similar. Customs unions tend to form between relatively well-endowed countries or those with similar preferences. It is also demonstrated that CUs will usually Pareto dominate FTAs, except where preferences differ significantly. The role of transfers in CU formation has received relatively little attention in the regionalism literature. In this thesis, optimal intra-union transfers are introduced and their impact on CET choice is investigated. The impact of transfers on CU behaviour depends on the direction of the transfer. When the relatively inelastic member is the recipient, the CU responds less aggressively to non-member tariff choices than it does when transfers are not permitted. However, if the relatively elastic member is the transfer recipient, the union's aggression increases. Moreover, when one union member exercises a similar degree of control over both CET and transfer choice, then the equilibrium CET tends to be lower than in the corresponding no-transfers situation.
39
Drake, Benjamin. "Public willingness to pay for local and global environmental benefits using choice modelling". Thesis, University of York, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.550265.
Testo completoAbstract (sommario):
Many environmental benefits exhibit non-excludability and non-rivalry characteristics akin to public goods. This makes it unlikely that such environmental benefits will attract a price in the marketplace. Policymakers therefore find difficulties in determining a correct economic valuation for environmental benefits exhibiting public good characteristics, leading to potentially severe consequences for aligning policy for the provision of environmental benefits with public preferences for service delivery. This research used a choice modelling approach to estimate public preferences for delivery of local and global environmental benefits; reductions in the flood risk to the British city of York (implemented by filling in drainage ditches in peat moorland further up the catchment), and a reduction in CO2 emissions (implemented by planting poplar trees for biomass either locally in the study area or elsewhere in the UK). The choice experiment presented respondents with options providing different levels of these environmental benefits with a tax as the payment vehicle. Analysis of choice experiment data revealed one latent class (LC) segment holding a significant preference for achieving a high level of CO2 reduction through national, as opposed to local tree planting, potentially indicating the existence of 'not in my backyard' (NIMBY) behaviour. Analysing the choice experiment data using the random parameter logit (RPL) model revealed mean annual public willingness to pay (WTP) estimates of £0.48-£9.55, £0.75-£14.91 and £30.93-£51.54 for levels of CO2 reduction through local and national tree planting, and flood risk reduction to York respectively. This research also quantifies the biophysical capacity to deliver levels of CO2 reduction in the choice experiment, using a combined literature review of biomass combustion characteristics and geographical information system (GIS) modelling. This indicates that national poplar tree planting can contribute towards year 2020 renewable electricity targets without greatly compromising on domestic agricultural production.
40
Agarwal, Shweta. "Beyond lucky : measuring and modelling the impact of 'probability control' on risky choice". Thesis, London School of Economics and Political Science (University of London), 2014. http://etheses.lse.ac.uk/1021/.
Testo completoAbstract (sommario):
Managers frequently deal with risk by considering uncertainty as an element of the decision problem over which they can exert control — for example, lobbyists trying to exert influence over regulators or managers trying to mitigate Operational Risks related to human processes. This perspective that the probabilities of uncertain events are at times ‘mutable’ — i.e. subject to one’s influence — has an important and previously under-appreciated role in decision-making under risk. The present research, structured as a series of three papers, addresses this gap between theory and practice on the topic of ‘control’ from a descriptive, theoretical and prescriptive perspective. The descriptive paper discusses a novel empirical test of the behavioural effect of ‘control’ on risk taking. The key finding that control does not always enhance risk taking but, instead, has a moderating effect on attitudes to risk, extends insights from related research. Strong preference for exerting control to eliminate uncertainty is also revealed. Affective and cognitive interpretations of the findings are offered and their correspondence with managerial attitudes to risk taking is discussed. The theoretical paper builds on methods in Decision Analysis and Philosophy, and develops a new probability revision rule for modelling control as interventions on uncertainties. This rule is shown to dramatically alleviate the judgmental burden of analysing multiple interventions. Foundational properties for probability revision rules for interventions, similar to the coherence criterion for Bayes rule, are also constructed and a proof that the proposed rule satisfies these properties is offered. In the prescriptive paper, a real world application of the probability revision rule is illustrated in the context of Operational Risk assessment, where several uncertainties are controllable (e.g. staff strikes). It is shown how this rule can be integrated with Operational Risk calculations to explicitly incorporate the effect of managerial mitigations on loss events, thus making a useful contribution to the field. In summary, this research explores the concept of ‘probability control’ as a way to manage risks in the context of Decision Sciences. It furthers our behavioural understanding of risk attitudes to better resonate with managerial perspectives on risk taking and extends the relevance of Decision Analysis methods to corporate risk management.
41
Pluntke, C. "Modelling users in networks with path choice : four studies in telecommunications and transit". Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1453276/.
Testo completoAbstract (sommario):
Networks of interacting users arise in many important modelling applications. Commuters interact with each other and form traffic jams during peak-time. Network protocols are users in a communication network that control sending rate and server choice. When protocols send with too high rates, network links get overloaded resulting in lost data and high delays. Although these two example users seem very different, they are similar on a conceptual modelling level. Accurate user models are essential to study complex interactions in networks. The behaviour of a user with access to different paths in a network can be modelled as an optimisation problem. Users who choose paths with the highest utility are common in many different application areas, for example road traffic, Internet protocol modelling, and general societal networks, i.e. networks of humans in everyday life. Optimisation-based user models are also attractive from the perspective of a modeller since they often allow the derivation of insights about the behaviour of the entire system by only describing a user model. The aim of this thesis is to show, in four practical studies from telecommunications and transit networks, where optimisation-based models have limitations when modelling users with path choice. We study users who have access to a limited number of paths in large scale data centers and investigate how many paths per user are realistically needed in order to get high throughput in the network. In multimedia streaming, we study a protocol that streams data on multiple paths and path properties matter. We also investigate complex energy models for data interfaces on mobile phones and evaluate how to switch interfaces to save energy. Finally, we analyse a long-term data set from 20,000 transit commuters and give insights on how they change their travel behaviour in response to incentives and targeted offers. We use tools from optimisation, simulation, and statistics to evaluate the four studies and point out problems we faced when modelling and implementing the system. The findings of this thesis indicate where user models need to be extended in order to be of practical use. The results can serve as a guide towards better user models for future modelling applications.
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Pawlak, Jacek, John W. Polak e Aruna Sivakumar. "A framework for joint modelling of activity choice, duration, and productivity while travelling". Elsevier, 2017. https://publish.fid-move.qucosa.de/id/qucosa%3A72810.
Testo completoAbstract (sommario):
Recent developments in mobile information and communication technologies (ICT), vehicle automation, and the associated debates on the implications for the operation of transport systems and for the appraisal of investment has heightened the importance of understanding how people spend travel time and how productive they are while travelling. To date, however, no approach has been proposed that incorporates the joint modelling of in-travel activity type, activity duration and productivity behaviour.
To address this critical gap, we draw on a recently developed PPS framework (Pawlak et al., 2015) to develop a new joint model of activity type choice, duration and productivity. In our framework, we use copulas to provide a flexible link between a discrete choice model of activity type choice, a hazard-based model for activity duration, and a log-linear model of productivity. Our model is readily amenable to estimation, which we demonstrate using data from the 2008 UK Study of Productive Use of Rail Travel-time. We hence show how journey-, respondent-, attitude-, and ICT-related factors are related to expected in-travel time allocation to work and non-work activities, and the associated productivity.
To the best of our knowledge, this is the first framework that both captures the effects of different factors on activity choice, duration and productivity, and models links between these aspects of behaviour. Furthermore, the convenient interpretation of the parameters in the form of semi-elasticities enables the comparison of effects associated with the presence of on-board facilities (e.g., workspace, connectivity) or equipment use, facilitating use of the model outputs in applied contexts.
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Fu, Qian. "Modelling route choice behaviour with incomplete data : an application to the London Underground". Thesis, University of Leeds, 2014. http://etheses.whiterose.ac.uk/8746/.
Testo completoAbstract (sommario):
This thesis develops a modelling framework for learning route choice behaviour of travellers on an underground railway system, with a major emphasis on the use of smart-card data. The motivation for this topic comes from two respects. On the one hand, in a metropolis, particularly those furnished with massive underground services (e.g. London, Beijing and Paris), severe passenger-traffic congestion may often occur, especially during rush hours. In order to support the public transport managers in taking actions that are more effective in smoothening the passenger flows, there is bound to be a need for better understanding of the passengers’ routing behaviour when they are travelling on such public transport networks. On the other hand, a wealth of travel data is nowadays readily obtainable, largely owing to the widespread implementation of automatic fare collection systems (AFC) as well as popularity of smart cards on the public transport. Nevertheless, a core limitation of such data is that the actual route-choice decisions taken by the passengers might not be available, especially when their journeys involve alternative routes and/or within-station interchanges. Mostly, the AFC systems (e.g. the Oyster system in London) record only data of passengers’ entry and exit, rather than their route choices. We are thus interested in whether it is possible to analytically infer the route-choice information based on the ‘incomplete’ data. Within the scope of this thesis, passengers’ single journeys are investigated on a station basis, where sufficiently large samples of the smart-card users’ travel records can be gained. With their journey time data being modelled by simple finite mixture distributions, Bayesian inference is applied to estimate posterior probabilities for each route that a given passenger might have chosen from all possible alternatives. We learn the route-choice probabilities of every individual passenger in any given sample, conditional on an observation of the passenger’s journey time. Further to this, the estimated posterior probabilities are also updated for each passenger, by taking into account additional information including their entry times as well as the timetables. To understand passengers’ actual route choice behaviour, we then make use of adapted discrete choice model, replacing the conventional dependent variable of actual route choices by the posterior choice probabilities for different possible outcomes. This proposed methodology is illustrated with seven case studies based in the area of central zone of the London Underground network, by using the Oyster smart-card data. Two standard mixture models, i.e. the probability distributions of Gaussian and log-normal mixtures, are tested, respectively. The outcome demonstrates a good performance of the mixture models. Moreover, relying on the updated choice probabilities in the estimation of a multinomial logit latent choice model, we show that we could estimate meaningful relative sensitivities to the travel times of different journey segments. This approach thus allows us to gain an insight into passengers’ route choice preferences even in the absence of observations of their actual chosen routes.
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Chmura, Thorsten. "Analyse, Modellierung und Simulationen von Routenwahlverhalten / Analyses, Modelling and Simulation of Route Choice Behaviour". Gerhard-Mercator-Universitaet Duisburg, 2005. http://www.ub.uni-duisburg.de/ETD-db/theses/available/duett-05152005-222337/.
Testo completoAbstract (sommario):
This thesis will give an overview about the connection of physics and economy in special view of human behavior in traffic scenarios. Main topic is the human decision making process in a two-route-choice scenario. In three main Experiments, human players had to decide between two routes which connect two cities. The first experiment is defined by a pure Nash-equilibrium and 18 participants, the second experiment is similar, but alternating construction sites on both routes were added. Experiment 1 and 2 are played over 200 periods. The third experiment is a minority game with mixed equilibria and 9 participants. Experiment 3 was played over 100 periods. Furthermore the first experiment was extended to a larger group of players up to 90 persons. For every experiment two treatments with 6 observations were played. The treatments differ in the given information to the participants before they choose between the two routes. In the first treatment the information about the own travel time was given, additionally in the second treatment the information about travel times on both routes were given. The second part of the thesis describes the statistical data and illustrates the results. Two main results are that the equilibrium was not stable in the experiments, the fluctuations persists to the end of every observation. Further on two player types were found and explained in this chapter. In the third part of this thesis an extended payoff-sum model is described and explained. Simulations using this reinforcement learning model were run and show the reproducibility of the empirical data. In the conclusions the main results are shown and discussed.
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Soopramanien, Didier Gerard Rodney. "Gender effects in the labour market : modelling the participation decision and the occupational choice". Thesis, Lancaster University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274205.
Testo completo
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Vosper, Jane. "Using stated preference choice modelling to determine treatment preferences : investigating preferences for depression treatment". Thesis, University of Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.559707.
Testo completoAbstract (sommario):
Background & Aim The PhD aimed to quantify preferences for depression treatments using Discrete Choice Experiments (DCEs). A secondary aim was to investigate the relationship between demographic variables, psychological variables and preferences. Methods & Analysis Two DCEs were designed and administered, investigating preferences for treatment of depression by: (1) a drug and (2) a physical activity intervention. The DCE designs were informed by focus groups and qualitative interviews. A best-worst scaling DCE was used for both studies. The physical activity intervention DCE was included in the baseline questionnaire of an RCT at the University of Bristol. Demographic information and psychological measures (including BDI scores) were analysed alongside the DCE. The drug treatment DCE was distributed as a postal questionnaire to a general population sample of 5000. Psychological measures of illness and medicine beliefs as well as the BDI were included in the questionnaire. Demographic data were also collected. Quantitative data were analysed primarily using conditional logistic regression. Results Results from the Physical activity DCE (for 152 patients) indicated that on average, patients particularly valued key aspects of the intervention, such as small goals, fitting activity into daily routine and having support over the intervention itself (being one giving choice of activity rather than exercise on prescription). Results from Drug study DCE (for 425 respondents) revealed a particular desire for no side-effects: large improvements in likely effectiveness are required to compensate respondents for non-zero risks of these. Heterogeneity analysis for both studies revealed effects of a number of demographic and psychological variables on preferences for attributes of depression treatment. Discussion Results of both studies are discussed in terms of their policy relevance and also from a methodological angle. The implications the results have on the use of DCEs in health care is considered.
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Paramita, Puteri. "Modelling commuters' mode choice: Integrating travel behaviour, stated preferences, perception, and socio-economic profile". Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/122227/1/Puteri_Paramita_Thesis.pdf.
Testo completoAbstract (sommario):
Understanding of the shift behaviours are critical to formulate effective policies to encourage mode shift and anticipate the increasing demands of public transport services impacted by the shifting behaviours. This study aims to investigate the mode choice behaviour of commuters by utilising the nation-wide survey of commuters in Australia and employing the state-of-the-art Multinomial Logit Models. This study has investigated three critical choice behaviours issues: commuters' satisfaction towards train fare, consistency between commuters' current behaviours against their future preferences, and policy interventions to influence mode shift. Its findings have demonstrated significant theoretical and practical contributions to the commuters' choice behaviours.
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Fifer, Simon James. "Hypothetical bias in Stated Preference Experiments: Is it a Problem? And if so, how do we deal with it?" Thesis, The University of Sydney, 2011. http://hdl.handle.net/2123/7923.
Testo completoAbstract (sommario):
The extent to which Stated Preference (SP) experiments suffer from hypothetical bias continues to be a controversial topic in the SP literature. This thesis provides further evidence in this debate by examining the existence of hypothetical bias in a transport-related SP experiment. Data for this thesis were sourced from a University of Sydney study exploring the effect of variable rate charging on motorist behaviour. The sample included 148 Sydney motorists who were recruited to take part in a 10-week GPS driving field study (Revealed Preference / RP data). In addition, participants were also required to complete an SP survey. The SP survey consisted of a Contingent Valuation (CV) and Choice Experiment (CE) task designed to mimic the RP decision context in order to capture what participants indicated they would do as opposed to what participants actually did in reaction to the charging regime. Hypothetical bias was established by examining important differences between what people said they would do in the SP experiment and what they actually did in the RP field study. The current state of practice for measuring hypothetical bias in the literature is to compare aggregate differences in model outcomes using SP and RP data sources. Aggregate analysis is limited in its scope and does not allow for the calculation of the prevalence of hypothetical bias (i.e., how many participants are affected by hypothetical bias) or give any insight into why hypothetical bias occurs (i.e., correlates of hypothetical bias). This research is uniquely structured to allow for individual categorisation of hypothetical bias by comparing SP and RP data from the same sample for the direct purpose of investigating the prevalence of hypothetical bias. Furthermore, the extent to which elicitation procedures (CV and CE), mitigation techniques (cheap talk and certainty scales), demographics (gender and age) and the level of experience influence hypothetical bias is also explored. The findings from this research show that the SP model estimates are prone to hypothetical bias and that the mitigation techniques have potential to compensate for this inherent bias.
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Balbontin, Camila. "Integrating Decision Heuristics And Behavioural Refinements Into Travel Choice Models". Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/17892.
Testo completoAbstract (sommario):
Discrete choice modelling has become the preferred empirical context to study individuals’ preferences and willingness to pay. Although the outcome is important in decision making, so is the process that individuals adopt to assist them in reaching a decision. Both should be considered when analysing individual behaviour as they represent jointly the endogeneity of choice. Traditional choice studies assume, in the main, a linear in the parameters additive in the attributes (LPAA) approach, where individuals are rational, take into account all the attributes and alternatives presented to them when reaching a decision, and value the attribute levels exactly as were presented in the popular choice experiment paradigm. This has not always been shown to be a behaviourally valid representation of choice response, and there is a growing literature on the role of a number of alternative decision process strategies that individuals use when facing a decision, which are often referred to as heuristics, or simply as process rules. The majority of choice studies also assume that respondents have a risk attitude that is risk neutral (i.e., a risky alternative is indifferent to a sure alternative of equal expected value) and that they perceive the levels of attributes in choice experiments in a way that suggests the absence of perceptual conditioning. Considering each in turn, there are people who are risk adverse, risk taking or risk neutral, and this heterogeneity in risk attitude does influence individuals’ decisions when faced with different choice scenarios. Heterogeneity is also present for perceptual conditioning in cases where there is variability in the outcomes of an attribute(s), which allows for differences between the stated probability of occurrence (in a choice experiment) and the perceived probability used when evaluating the prospect. Finally, the (accumulated) experience that individuals’ have with each alternative might also influence their decisions. The objective of this research is to integrate multiple decision process strategies, Value Learning (VL) and Relative Advantage Maximisation (RAM) in particular, alongside the traditional LPAA ‘process rule’ with behavioural refinements (i.e., risk attitudes, perceptual conditioning and overt experience), to take into account process endogeneity in choice responses. A novel approach is used to include process heterogeneity, referred to as conditioning of random process heterogeneity, where the mean and standard deviation of the parameters normally defined under an LPAA heuristic are conditioned by process strategies. This approach takes into account the relationship between process heterogeneity and preference heterogeneity, of particular interest in studies that integrate random parameters and process strategies. The model performance results and willingness to pay estimates are compared to those obtained when using a probabilistic decision process method, increasingly used in the choice literature to accommodate process heterogeneity.
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Richter, Vide. "Transport Choices and Vehicle Ownership with Autonomous Vehicles : A modelling effort on car ownership, transport mode choice and travel demand with Driverless Technology". Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-233863.
Testo completoAbstract (sommario):
Transport is one of the basic needs of a functioning society. Unfortunately, transport also pollutes our cities and release greenhouses gases. Driverless technology is a technology predicted to disrupt the future transport system, and perhaps change how we travel from private cars to shared vehicles. This study focuses on the aspect of privately owned versus shared driverless vehicles, to create more knowledge of how the future transport system will look. A utility-based demand model is used to find the demand for private and shared transport when driverless vehicles are available. The utility of different transport options is estimated by looking at earlier studies about the performance of driverless cars, driverless buses and shared driverless taxis, which is used as input for the utility model. The results indicate that driverless technology will not be a catalyst that makes transport go from private to shared. While driverless buses can improve public transport, and shared driverless taxis outcompete current taxis, driverless technology will also improve private vehicles. The results in this study imply that the sustainability improvements earlier reports have predicted with a high use of shared driverless transportation might not materialise unless efforts are done to increase use of shared transportation.Transport är ett av de grundläggande behoven för ett välfungerande samhälle. På samma gång släpper transporter ut både växthusgaser och skadliga partiklar. Självkörande teknik är något som förväntas revolutionera framtidens transportsystem, förhoppningen är att de ska förändra hur folk reser från privata bilar till delade transporter. Denna studie fokuserar på den förhoppningen. Kommer framtidens transporter ske i privata självkörande fordon eller delade självkörande fordon och vad i sin tur betyder det för framtidens transportsystem? Med en nyttobaserad efterfråge- och bilinnehavsmodell modelleras efterfrågan av självkörande delade taxis, självkörande bussar och självkörande privatbilar. Resultaten indikerar att självkörande teknik inte nödvändigtvis kommer vara en katalysator som får människor att sluta äga och använda privatbilar. Självkörande bussar kan göra kollektivtrafiken bättre, och självkörande delade taxibilar kommer troligtvis användas mer än dagens taxis. Men självkörande privatbilar kommer också ha många fördelar, och de som äger dem kommer dessutom troligtvis köra längre sträckor än dagens bilister. Resultatet av denna rapport indikerar därför att de stora förväntningarna som finns på självkörande teknik gällande delade transporter kan vara felaktiga, om inte andra åtgärder också görs för att öka delning. Att delningen inte ökar gör också att de hållbarhetsförbättringar som vissa tidigare rapporter förutspått inte nödvändigtvis kommer ske.