Après une introduction générale et une revue de littérature (chapitre 1), l’apport de cette thèse est de déterminer le rôle de la demande dans l’émergence d’un stock de marchandises invendues. Les préférences des consommateurs sont modifiées puisqu’elles prennent en compte non seulement les quantités consommées mais également celles étalées. Le cadre d’analyse de cette thèse est celui d’un jeu stratégique à deux joueurs en univers certain, avec prix flexibles et information parfaite. Deux types de consommateurs sont considérés : certains apprécient l’étalage et d’autres non. Un monopole modifié choisit à la fois le prix et l’étalage. Les propriétés de l’équilibre de Nash en stratégies pures sont étudiées. Le chapitre 2 présente un modèle de détermination du mark-up optimal pour n’importe quelle valeur de l’élasticité prix de la demande (contrairement à l’indice de Lerner qui peut être utilisé uniquement pour les biens élastiques). Le chapitre 3, étend le second, en déterminant le coefficient multiplicateur optimal en présence de stocks d’invendus. Il permet de définir la solde optimale. Le quatrième et dernier chapitre détermine les conditions sur les fonctions d’utilité qui permettent de générer un stock d’invendus à l’équilibre de Nash en stratégies pures. Les modèles développés sont élargis au cas où un planificateur social intervient dont l’objectif est de maximiser le bien-être de l’économie. / After a general introduction and a survey of literature, the contribution of this thesis is to determine the role of the demand in the emergence of unsold stock of goods based on consumer’s preferences argument. Throughout the thesis, we consider a strategic game with two players under perfect information, certainty and price flexibility. Consumers are of two types: with appreciation to the display and without. A modified monopoly chooses both the price and the display. Chapter 2 presents an original model to determine the optimal markup for both elastic and inelastic goods (unlike the Lerner index that is used only for elastic goods). Chapter 3 is an extension of the previous one. It is about the determination of an optimal markup with the presence of unsold stock of goods. The fourth and final Chapter analyzes under which conditions an unsold stock of goods is supported by a pure strategy Nash equilibrium. All the models developed present a welfare analysis.

La théorie économique standard postule que les préférences individuelles sont stables. Cependant, de nombreux résultats en psychologie et en économie expérimentale montrent que le comportement humain contrevient régulièrement à ce principe fondamental. Certains facteurs connus pour influencer la valeur, comme le contexte affectif, ne sont pas pris en compte en économie. Leurs effets sont encore considérés comme des phénomènes contingents– des anomalies en marge de la rationalité, qui en tant que telles n’informent pas la théorie. Aujourd’hui que l’imagerie cérébrale permet de formuler et tester de nouvelles hypothèses, nous interrogeons le caractère contingent de l’influence du contexte sur les préférences, avec en tête l’idée que ces « biais » découleraient de propriétés inhérentes à la structure physique qui génère le comportement, à savoir le cerveau. Parce qu’ils reflètent les conditions a priori de tout jugement de valeur, ils ne sont pas contingents mais nécessaires, ce qui explique leur prévalence. Notre première étude fait la preuve de cette hypothèse dans le cas des biais de contexte : nous montrons que l’inertie de l’activité cérébrale combinée à l’automaticité de l’évaluation permet d'expliquer les effets du contexte sur la valeur chez le singe et l’être humain. Notre deuxième étude montre que la confiance est codée dans la même région cérébrale que la valeur, suggérant que la peut être comprise comme un jugement de valeur de second ordre. Enfin, notre troisième étude montre un biais d’attribution comportemental menant à des interférences entre valeur et confiance, ce qui était prédit par la combinaison des résultats de la première et de la deuxième étude. / Standard economic theory postulates that individual preferences are stable. However, numerous psychology and experimental economics findings show this fundamental principle is often violated in actual human behavior. Some factors known to influence value, such as affective context, are not taken into account. Their effects are still considered contingent phenomena – anomalies observed on the margins of rationality – and as such do not inform economic theories. As modern neuroimaging techniques enable us to formulate and test new hypotheses, we propose to examine the contingent nature of this instability, in the light of the idea that these "biases" are in fact directly related to the inherent properties of the physical structure that generates behavior, namely the brain. Because they reflect the a priori conditions of any value judgment, they are not contingent but necessary, which explains their prevalence in observed behavior. Our first study proves this hypothesis in the case of context‐induced valuation biases: we show that the inertia of cerebral activity combined with the automaticity of evaluation can explain the effects of context on valuation in macaque monkeys and humans. Our second study shows that confidence is encoded in the same brain region as value in humans, suggesting that confidence judgments can be understood as second‐order value judgments. Our third study behaviorally demonstrates an attribution bias leading to interferences between value and confidence judgments, as predicted by combining the results of the first and the second study in humans.

The act of reading has benefits for individuals and societies, yet studies show that reading declines, especially among the young. Recommender systems (RSs) can help stop such decline. There is a lot of research regarding literary books using natural language processing (NLP) methods, but the analysis of textual book content to improve recommendations is relatively rare. We propose content-based recommender systems that extract elements learned from book texts to predict readers’ future interests. One factor that influences reading preferences is writing style; we propose a system that recommends books after learning their authors’ writing style. To our knowledge, this is the first work that transfers the information learned by an author-identification model to a book RS. Another approach that we propose uses over a hundred lexical, syntactic, stylometric, and fiction-based features that might play a role in generating high-quality book recommendations. Previous book RSs include very few stylometric features; hence, our study is the first to include and analyze a wide variety of textual elements for book recommendations. We evaluated both approaches according to a top-k recommendation scenario. They give better accuracy when compared with state-of-the-art content and collaborative filtering methods. We highlight the significant factors that contributed to the accuracy of the recommendations using a forest of randomized regression trees. We also conducted a qualitative analysis by checking if similar books/authors were annotated similarly by experts. Our content-based systems suffer from the new user problem, well-known in the field of RSs, that hinders their ability to make accurate recommendations. Therefore, we propose a Topic Model-Based book recommendation component (TMB) that addresses the issue by using the topics learned from a user’s shared text on social media, to recognize their interests and map them to related books. To our knowledge, there is no literature regarding book RSs that exploits public social networks other than book-cataloging websites. Using topic modeling techniques, extracting user interests can be automatic and dynamic, without the need to search for predefined concepts. Though TMB is designed to complement other systems, we evaluated it against a traditional book CB. We assessed the top k recommendations made by TMB and CB and found that both retrieved a comparable number of books, even though CB relied on users’ rating history, while TMB only required their social profiles.

This thesis studies the labour supply with aspiration-based reference-dependent preferences. The first contribution of the thesis is the theoretical modelling of behavioural contract theory. In Chapter 1, I modify the classical principal-agent model with uncertainty and moral hazard by replacing the Expected Utility preferences of the agent with chance theory preferences (Schmidt and Zank, 2013). Chance theory agents are primarily concerned with the sure wage they can obtain, i.e., the certain component in their contract, as they treat increments in bonuses markedly different to similar changes in sure wages. Similar to the classical predictions, our agents' optimal contracts are contingent payment schemes, however, they differ with respect to the level of the sure wage. I also contrast my predictions to those of the model of Herweg et al. (2010), who assume agents with expectation-based loss-averse preferences. The other contribution of this thesis is the empirical support for the theory of aspiration-based reference-dependent preferences with field data in education economics. In Chapter 2, I study aspiration-based reference-dependent preferences in undergraduate students' performance and effort provision. Students' reference points are set as their targeted grades. I extend a two-period economics-of-education model (Krohn and O'Connor, 2005) by proposing an additional utility function that is based on the difference between the realised grade and targeted grade. I design surveys and collect data by following a group of undergraduate students at the University of Manchester for two semesters of a full academic year with a two-period panel. My results provide evidence for students' reference-dependent preferences in two ways: first, a significant jump in students' proxied utility of grade is found at the reference point, which also implies students are loss averse. Second, the reference point positively affects students' effort provision. I further study the formation of the reference point and its variation over time. My results suggest that students partially update their past realised results into the formation of reference points. Further, the relative change of their reference points depends on the achievement of the past period reference point.

"June 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 138-148). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest dissertations and theses, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

O presente trabalho desenvolve um modelo capaz de descrever preferências dependentes de contexto, buscando superar as limitações impostas pela abordagem da preferência revelada. O espaço informacional no ato da escolha é ampliado através da incorporação de uma segunda dimensão, na forma de um novo tipo de utilidade, dita social ou moral, representativa do contexto no qual a escolha é realizada. As dimensões são assumidas incomensuráveis entre si, uma característica típica de escolhas que envolvem questões morais. A impossibilidade de comparação entre duas alternativas, cada qual superior à outra em uma dimensão distinta, é resolvida através de uma simetria rotacional capaz de preservar a relação sujacente entre ambas utilidades. O modelo é baseado, fundamentalmente, nos trabalhos de Amartya Sen (1974, 1977, 1993, 1997) e Amitai Etzioni (1986), incorporando conceitos de utilidade moral (ETZIONI, 1986), dependência de contexto no ato da escolha (SEN, 1993, 1997), inescapabilidade ou urgência da escolha (SEN, 1997), auto-imposição de limites à escolha (SEN, 1997; ETZIONI, 1986), commitment, entendido como divisão entre escolha e bem-estar (SEN, 1977) e flexibilidade cognitiva dos indivíduos (ARIELY, 2012). / In this work, we develop a model that is able to describe context-dependent preferences, trying to overcome the limitations given by the revealed preference approach. The informational space in the act of choice is broadened by incorporating a second dimension, as a new type of utility, called social or moral, representing the context within the choice is made. The dimensions are deemed incommensurable, a typical characteristic of moral-related choices. The impossibility of comparison between two alternatives, where each alternative is the superior one in a different dimension, is resolved through a rotational symmetry able to preserve the underlying relationship between the two utilities. The model is fundamentally based on the works of Amartya Sen (1974, 1977, 1993, 1997) and Amitai Etzioni (1986), making use of the concepts of moral utility (ETZIONI, 1986), context-dependency in the act of choice (SEN, 1993, 1997), inescapability or urgency of the choice (SEN, 1997), self-imposing limits to choice (SEN, 1997; ETZIONI, 1986), commitment, understood as a wedge between choice and welfare (SEN, 1977) and the cognitive flexibility of the individuals (ARIELY, 2012).

No description available.

Cette thèse se compose de trois chapitres constituant des contributions distinctes mais reliées au même centre d'intérêt, la théorie de la décision dans le risque. Le premier chapitre traite de préférences additivement séparable par rapport aux probabilités. Il en est déduit une axiomatisation simple de préférences variationnelles représentées par une fonctionnelle se décomposant en un terme d'espérance d'utilité et un terme entropique. Le second chapitre consiste en une fondation axiomatique de préférences interdépendantes en présence d'interactions sociales, sur la base du modèle initialement élaboré par Blume, Brock et Durlauf. Le troisième chapitre pose la question de l'apport du modèle probabiliste de la physique quantique à la théorie de la décision et de son application pour prendre en compte la perception subjective des évènements par les individus. / This thesis consists of three separate chapters related to economic decisions under risk. The first chapter presents axioms for an additively separable representation of preferences over probabilities. A simple axiomatization of variational preferences represented by the sum of an expected utility term and an entropic term is deduced. The second chapter consists of an axiomatic foundation of other-regarding preferences under social interactions, based on the model originally developed by Blume, Brock and Durlauf. The third chapter introduces the probabilistic model of quantum physics to decision theory. In this context, individuals have a private representation of the set of events.

FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / nÃo hà / Estudo sobre educaÃÃo do gosto alimentar construÃdo por meio de prÃticas curriculares e cotidianas de uma escola da rede pÃblica estadual do PiauÃ, localizada na cidade de Teresina, considerando a relaÃÃo currÃculo, prÃtica alimentar, cotidiano escolar e educaÃÃo para o gosto alimentar. A metodologia teve base etnogrÃfica, conjugando abordagens de natureza qualitativa e quantitativa. Ocorreu em uma escola da rede pÃblica estadual de ensino, em Teresina/PI, da qual participaram alunos e pais de alunos, docentes e funcionÃrios, alÃm de moradores e comerciantes da alimentaÃÃo da regiÃo prÃxima à escola. A coleta de dados se deu por meio de: observaÃÃo do cotidiano escolar; entrevistas semi-estruturadas, fundamentadas na HistÃria Oral; QuestionÃrio de FreqÃÃncia do Consumo Alimentar (QFCA). Os dados quantitativos foram prÃ-analisados, estatisticamente pelo programa GraphPad Prism para estimar aspectos da educaÃÃo do gosto alimentar, especificando os variados gÃneros alimentÃcios consumidos; os dados qualitativos foram examinados a partir dos fundamentos da HermenÃutica de Profundidade que consta de: anÃlise sÃcio-histÃrica; anÃlise formal ou discursiva; e interpretaÃÃo/ reinterpretaÃÃo. Os resultados indicam: duas dimensÃes da educaÃÃo do gosto alimentar, sendo uma relacionada ao currÃculo instituÃdo na escola e outra voltada para o currÃculo oculto, expresso no cotidiano escolar; a disciplina Horta Escolar no currÃculo da escola estudada, ensejou experiÃncias sensoriais, lÃdicas e de vÃnculo com os alimentos naturalmente cultivados na escola, como estratÃgia para estimular o consumo de alimentos saudÃveis e de ampliaÃÃo do conhecimento acerca da procedÃncia dos gÃneros alimentÃcios a serem consumidos. No cotidiano escolar, as prÃticas alimentares se destacam, uma vez que nÃo alÃm de serem apresentados modelos saudÃveis de alimentaÃÃo nas quatro refeiÃÃes oferecidas da escola, priorizam as socializaÃÃes realizadas e mediadas pelas prÃticas alimentares, os vÃnculos construÃdos, as aplicaÃÃes prÃticas dos conhecimentos estudados acerca da alimentaÃÃo, preconizando a sensibilizaÃÃo dos alunos para um consumo alimentar consciente e promotor do bem-estar por meio da alimentaÃÃo saudÃvel. As vertentes identificadas constituem um processo formativo da educaÃÃo do gosto alimentar nos escolares, fomentando, sobretudo, o consumo de hortaliÃas e frutas, que quase dobra com a experiÃncia vivida de um ano letivo. Constatou-se a reduÃÃo de mais de 50% do consumo semanal de aÃÃcares e frituras, com substancial aumento do consumo de carne branca. Houve diminuiÃÃo da predisposiÃÃo por alimentos enlatados e progressiva minimizaÃÃo do consumo de carne vermelha, salgadinhos, vÃsceras e Ãleos. Enfim, evidenciou-se que para desenvolver a educaÃÃo do gosto alimentar como processo formativo a ser construÃdo tambÃm na escola, à indispensÃvel a integraÃÃo de trÃs Ãreas: educaÃÃo/currÃculo, alimentaÃÃo/nutriÃÃo e ambiente escolar/comunidade. / This study assessed the education of food preferences that are constructed from curricular and everyday practices at a public school in Teresina. It examined the relationship between the curriculum, eating practices, daily school life and education about food preferences. Using an ethnographically-based methodology, the study combined qualitative and quantitative approaches. It took place in a public state school in Teresina, Piaui. Students, parents of students, teachers and school workers participated in the study, as well as residents and food sellers in the school vicinity. Data were collected by observation of the school routine, semi-structured interviews based on oral history, and a Questionnaire of Food Consumption Frequency (QFCF). Quantitative data were statistically analyzed using GraphPad Prism to estimate aspects about the education of food preferences and the different types of foods consumed. Qualitative data were examined using principles of Depth Hermeneutics, and consisted of: socio-historical analysis; formal or discursive analysis; and interpretation/reinterpretation. The results indicated that there were two dimensions of education on food preferences: the school curriculum and the concealed curriculum that is expressed in daily school life. The School Allotment, a subject that forms part of the school curriculum, encourages sensory, playful and bonding experiences with foods that are grown at school, and this strategy encourages consumption of healthy food and increases knowledge about the origin of food products. In daily school life, eating practices are particularly important: they not only provide healthy eating models in the four meals offered at the school, but they also prioritize socialization, bonding with food, are a way of practically applying the knowledge that has been acquired about food, and advocate the conscious consumption of food by the students to promote wellness through healthy eating. The identified educational dimensions are part of a formative process of the education of food preferences of students, and stimulate the consumption of vegetables and fruit (which nearly doubled during the course of a school year). There was a more than 50% reduction of weekly consumption of sugars and fried food and a substantial increase in the consumption of white meat. There was also a reduction of canned foods and a gradual minimization of the consumption of red meat, snack foods, animal organs and oils. It was clear that in order to develop the education for food preferences as a formative process that can be constructed at school, it is essential to integrate three areas: education/curriculum, food/nutrition and school environment/community.

O presente estudo, realizado em escolas de Primeiro Grau do município de são Paulo, teve por objetivo investigar os motivos pelos quais os escolares assistem à televisão, suas preferências, tempo dispendido em assistir a seus programas, horário de maior audiência, quem costuma ligar o televisor nos programas a que o escolar assiste, liberdade e orientação dada pelos pais para assistir a estes programas e opinião do escolar sobre o caráter educativo dos programas. O trabalho compara também o tempo dispendido com a televisão e o tempo gasto em outras atividades. Os dados consideram as variáveis idade, sexo do escolar, bem como o nível sócio-econômico da família. Recomendações àqueles que pretendem utilizar a televisão como método de Educação em Saúde são apresentadas. / This paper reports a research carried out in Schools in São Paulo City with the objective to provide data on the factors motivating students to watch television programs, amount of time spent watching television, favorite programs and watching time. The study provides information on who usually turns the television on, permission and orientation given by parents to children concerning television programs and students\' opinion on their educational value. It compares time spent with television and other activities. Consideration was given to age and sex of children involved, as well as to the socioeconomic status of the family. The author makes recommendations to those who intend to utilize television as a method of Health Education.