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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Household income pooling and the demand for food: does family financial structure matter?

Perusquia Corres, Ernesto 02 June 2009 (has links)
Research on food consumption and expenditures usually employs the use of unitary models that do not account for type of family financial structure. This research presents two collective models of household behavior, conditional and unconditional models, which were used in the analysis of the household data that came from the “Parental Time, Role Strain and Children’s Fat Intake and Obesity Related Outcomes”. This research utilized the Generalized Method of Moments in the estimation of the system of expenditures on food at and away from home to test the validity of the unitary model by testing one of the implications of this model, the income pooling hypothesis, as well as family financial structure. It was found that the omission of family financial structure and not the income pooling hypothesis would lead to the incorrect assertion that the unitary model is the correct model for the analysis of intrahousehold allocation. The collective models proposed in this research were found to be preferred to those of the unitary models. These two models, conditional and unconditional, not only allow for the effect of earned and unearned incomes of fathers and mothers to be different, but also incorporate family financial structure into the analysis of expenditures on food at and away from home. This research shows that the parameters of the unitary models are reduced form parameters that do not represent the effect that the variable of interest has on the household expenditures category of interest. This research finds that these reduced form parameters show the total effect which is composed of three parts. First, the change in the expenditure category of interest that comes about from a change in the variable of interest when we hold family financial structure constant. Second, the change in the expenditure category of interest that comes about from a change in the family financial structure. Third, the change in family financial structure that comes about from a change in the variable of interest.
2

Generator Matrix Elements for Noncompact Sp(6) in a Sp(2) X 0(3) Basis

Niculescu-Sanielevici, Mihaela 02 1900 (has links)
No description available.
3

Studies of Triaxial Rotors and Band Mixing in Nuclei

Allmond, James Mitchell 06 April 2007 (has links)
Rigid rotor models were investigated with constraints from data for even-even nuclei. Specifically, from precision gamma-ray intensity measurements for 166-Er (from 166m-Ho and 166-Tm beta decays); from B(E2) systematics; and for 186,188,190,192-Os matrix element data.
4

Family, marriage markets and inequality : a matching approach / Famille, marché du mariage et inégalités : l'approche par les modèles d'appariement

Weber, Simon 14 September 2017 (has links)
Cette thèse traite de la formation des couples sur le marché du mariage, et propose comme fil directeur de s’intéresser à la question des inégalités, à la fois inter- et intra-ménages. Le premier chapitre interroge le rôle des préférences maritales dans la hausse des inégalités de revenu entre ménages. Edoardo Ciscato et moi-même utilisons des données américaines pour mesurer l’impact du changement des préférences maritales sur les inégalités de revenu entre ménages. Grâce à des méthodes structurelles, nous montrons que si les préférences maritales n’avaient pas changé depuis 1971, le coefficient de Gini aujourd’hui serait inférieur de 6%. Dans le chapitre 2, j’introduis l’idée de rapprocher la littérature sur les modèles d’appariement et celle sur les modèles collectifs. Pour cela, Alfred Galichon, Scott Kominers et moi-même avons travaillé sur un modèle d’appariement à utilité imparfaitement transférable. Nous prouvons l’existence et l’unicité de l’équilibre dans ce cadre. En outre, nous construisons deux algorithmes permettant de déterminer l’équilibre. Nous montrons comment le modèle peut être estimé par maximum de vraisemblance et proposons une illustration. Dans le dernier chapitre, je me concentre sur le partage des ressources au sein des couples. L’idée est que les modèles collectifs sont inséparables du marché du mariage, au sens où le partage du pouvoir de négociation est endogène à la détermination d’un équilibre sur le marché du mariage. Je discute de manière approfondie la connexion entre modèles collectifs et modèles d’appariement. En particulier, je caractérise les classes de modèles collectifs qui peuvent être intégrer au modèle d’appariement à utilité imparfaitement transférable (ITU) développé précédemment. Je propose une méthode générale pour estimer ces modèles. Enfin, je propose d’illustrer mes résultats sur des données extraites du PSID américain, et d’estimer un modèle avec consommation privée, loisir et travail domestique. / This dissertation deals with couple formation on the marriage market, and adopts a perspective that focuses on inequality both at the between- and within-household levels. Chapter 1 deals with the role of marital preferences on growing income inequalities between households. Edoardo Ciscato and I use mating patterns in the United States from 1962 to 2015 to measure the impact of changes in marital preferences on between-household inequality. Using structural methods, we show that if mating patterns had not changed since 1971, the 2015 Gini coefficient between households would be lower by 6%. In chapter 2, I propose to bring together the literature on matching models and collective models. To do so, Alfred Galichon, Scott Kominers and myself construct a matching framework with imperfectly transferable utility. We show existence and uniqueness of equilibrium and provide two algorithms to compute the equilibrium. We also provide guiding steps for estimation by maximum likelihood as well as an empirical illustration. Chapter 3 explores further the integration of collective models into the ITU matching framework. I develop the idea that the distribution of bargaining power is endogenous to the determination of an equilibrium on the marriage market. I characterize classes of collective models that can be embedded in the ITU setting. I provide computational techniques to estimate these models. I provide a full application of my results using collective model that features private consumption, leisure and a public good produced from time inputs.
5

Analyzing Rotational Bands in Odd-Mass Nuclei Using Effective Field Theory and Bayesian Methods

Alnamlah, Ibrahim Khaled I. 16 September 2022 (has links)
No description available.
6

Sur l’interdépendance entre localisation résidentielle et localisationprofessionnelle : modèles de choix discrets / On the Interdependence between Residential and Workplace Location : DiscreteChoice Models

Inoa-Peña, Ignacio 29 April 2015 (has links)
Cette thèse se concentre sur l'interdépendance entre les choix de localisation résidentielle et professionnelle. Des questions telles que le processus de prise de décision, l'accessibilité à l'emploi, la répartition géographique des emplois, et le prise de décision collective des conjoints, entre autres, sont analysées en développant des modèles de choix discrets. Dans ce cadre, nous étudions les choix de localisation à partir de deux points de vues complémentaires. (1) Premièrement, nous étudions l'interdépendance entre les deux choix de localisation sans considérer le processus de décision au sein des ménages. Nous développons un modèle logit emboîté à trois niveaux, pour les choix de localisation résidentielle et professionnelle et nous étudions l'effet des mesures d'attractivité et d'accessibilité spécifiques à chaque individu (log-sommes). Les résultats du premier chapitre montrent que l'accessibilité spécifique à chaque individu est un facteur déterminant du choix de localisation résidentielle et que son effet diffère le long du cycle de vie des ménages. L'attractivité des types d'emploi est un meilleur indicateur du choix de localisation professionnelle que le nombre d'emplois. L'évolution des mesures d'attractivité et d'accessibilité aux emplois est analysée dans le deuxième chapitre. (2) Deuxièmement, nous étudions l'interdépendance de la localisation résidentielle et professionnelle au sein du ménage. Cette thèse contribue à la littérature des modèles collectifs en développant un modèle de choix avec processus de négociation au sein des ménages à la Chiappori, pour décrire le choix de localisation résidentielle des ménages bi-actifs. Le dernier chapitre développe et estime un modèle structurel en deux étapes pour faire la part des choses entre le pouvoir de négociation et les valeurs du temps des conjoints. Les résultats montrent que les nationalités du couple, leur niveau d'éducation, ainsi que la différence d'âge entre les conjoints jouent un rôle crucial dans la détermination de pouvoir de négociation. / This thesis studies the interdependency between the choices of residential and workplace location. Issues such as the decision-making process, the accessibility to jobs, the geographical distribution of job types, and the spouses collective decision process, among others, are analyzed with discrete choice models. In this setting, we study the location decisions from two complementary points of view. (1) First, we study the interdependency between the two location choices without any within-household consideration. We develop a three-level nested logit model of residential and workplace location and study the effect of individual-specific attractiveness and accessibility (log-sum) measures. Results presented in the first chapter show that the individual-specific accessibility measure is an important determinant of the choice of residential location and its effect differs along the household life cycle. Additionally, the attractiveness of the types of employment is a better predictor of the workplace location than the usual total number of jobs. We analyze the evolution of the attractiveness and attractivity measures in the second chapter. (2) Second, we study the interdependency of residential location and workplaces within the household. This thesis contributes with a within-household bargaining process model of location decisions. As such, it applies the collectiveapproach à la Chiappori of household behavior to describe residential location choice of two-worker households. The last chapter develops and estimates a two-step structural model to disentangle bargaining powers from spouses' values of time. Results show that the nationalities of the couple, their education level, as well as the age difference between spouses play a crucial role in determining bargaining power.
7

Income shocks, household job search and labor supply / Choques de renda, procura familiar por emprego e oferta de trabalho

Gonçalves, Solange Ledi 07 June 2017 (has links)
Analyses about aggregate employment, unemployment, and inactivity rates frequently disregard labor market trends of specific household members, which may explain some puzzles in the relationship between economic activity and labor market participation. The relevance of family approaches of labor supply transcends the aggregate macroeconomic trends and addresses important micro-level analysis concerning the behavior and intrahousehold decisions of members and policy-relevant results. Despite the consensus about the joint labor supply decisions of household members, studies are typically at the individual level and disregard sons and daughters as decision-makers in a family. Therefore, in this thesis, we investigate these questions for Brazil, in two studies. In the first study, we analyze the labor supply decisions of sons daughters aged 14 to 24 years living with their parents, in a reduced form exercise. We collaborate to the empirical literature about intrahousehold impacts of policies, testing whether the minimum wage, which affects the income of parents, impacts the final labor supply decisions of sons and daughters. We also verify if the policy has distinct effects depending on whether the eligible person is the father or the mother, aiming to test the income-pooling hypothesis. Our identification strategy is based on an intention-to-treat approach, and in a differences-in-differences estimator. Another innovation is the use of the PNADC (IBGE) for 2012-2016. We find that the direction and magnitude of the minimum wage effects affecting fathers and mothers, on the labor supply of sons and daughters, depend on who is and how many eligible members there exist in the household: it is negative, whether the eligible person is the mother or the father, and it is positive, whether both are eligible. Therefore, our results strengthen the argument in favor of household approaches, since the income pooling hypothesis does not seem to be valid in this context. In the second study, we investigate how the decisions about labor supply could determine the aggregate results of unemployment and inactivity of the secondary household earners. We develop and estimate a structural household job search model with on-the-job search. We extend Dey and Flinn (2008) to allow for unemployment and inactivity of mothers and sons and daughters who are subject to shocks to their employment and income shocks to fathers. These shocks may determine different search behavior and job acceptance, depending on the other household member\'s labor market situation. The model is estimated using the PME (IBGE) for 2004-2014. We perform counterfactual simulations, and we verify that the decreasing unemployment rate of sons/daughters would not have changed between 2004 and 2014 if the labor market opportunities and conditions of this member remain the same. The unemployment rate of mothers does not alter a lot in this period. The increasing trend in the inactivity of sons/daughters is mostly determined by a decreasing encouragement rate and the increasing dropout rate observed among these members in this period. These exogenous factors that determine the move to or the permanence in the inactivity could be related to the lower cost of education. We conclude that the use of individual job search models to understand aggregate unemployment and inactivity can be misleading, since the household search behavior matters in the labor supply decisions of secondary household earners. / As análises sobre taxas agregadas de emprego, desemprego e inatividade frequentemente ignoram a dinâmica dos membros das famílias no mercado de trabalho, a qual pode explicar puzzles na relação entre atividade econômica e participação no mercado de trabalho. A relevância das abordagens familiares para a oferta de trabalho está nas análises macroeconômicas sobre tendências agregadas, e também em análises microeconômicas do comportamento, decisões intrafamiliares e resultados de políticas. Apesar do consenso sobre as decisões conjuntas de oferta de trabalho dos membros da família, grande parte dos estudos são abordagens individuais e desconsideram filhos jovens como tomadores de decisão. Nesta tese, organizada em dois estudos, investigamos essas questões para o Brasil. No primeiro estudo, analisamos a decisão de ofertar trabalho de jovens entre 14 e 24 anos vivendo com os pais, em um exercício de forma reduzida. A tese colabora com a literatura empírica sobre os efeitos intrafamiliares de políticas, ao testar se o salário mínimo que afeta a renda dos pais impacta a decisão final dos filhos de ofertar trabalho. Também testamos a hipótese de agregação da renda, ao verificar se se a política tem efeitos distintos caso a pessoa elegível na família seja a mãe ou o pai. A estratégia de identificação é baseada em uma abordagem de intention-to-treat, e no uso do estimador de diferenças-em-diferenças. Outra inovação é o uso da PNADC (IBGE) para 2012-2016. Verificamos que a direção e a magnitude dos efeitos do salário mínimo dos pais, na oferta de trabalho dos filhos, dependem de quem é e de quantos são os membros elegíveis na família: o efeito é negativo, se a pessoa elegível é a mãe ou o pai, e é positivo, se ambos são elegíveis. Esses resultados reforçam o argumento em favor das abordagens intrafamiliares, uma vez que a hipótese de income-pooling não parece ser válida neste contexto. No segundo estudo, investigamos como as decisões de oferta de trabalho poderiam determinar os resultados agregados de desemprego e inatividade dos membros secundários. Desenvolvemos e estimamos um modelo estrutural de busca por emprego familiar com on-the-jobsearch. Estendemos o modelo de Dey e Flinn (2008), para permitir desemprego e inatividade de mães e filhos, sujeitos a choques em seus empregos e choques na renda dos pais. Esses choques podem determinar diferentes comportamentos de busca e aceitação de emprego, dependendo da situação do outro membro no mercado de trabalho. O modelo é estimado com a PME (IBGE) para 2004-2014. Realizamos simulações contrafactuais e verificamos que a taxa de desemprego dos filhos, decrescente entre 2004 e 2014, não teria se alterado no período, caso as condições e oportunidades de mercado de trabalho dos filhos tivessem continuado as mesmas de 2004. Já a taxa de desemprego das mães não sofre grandes alterações no período. A tendência crescente na inatividade dos filhos é determinada por uma taxa de encorajamento decrescente e uma taxa de desistência crescente, que refletem fatores exógenos que levam jovens trabalhadores à inatividade. Esses fatores exógenos podem estar relacionados ao menor custo da educação no período. Concluímos que o uso de modelos individuais de busca por emprego para entender o desemprego e a inatividade agregados deve ser desencorajado, pois o comportamento de busca familiar importa para as decisões de oferta de trabalho dos membros secundários da família.
8

Collective Structure of Neutron-Rich Rare-Earth Nuclei and Development of Instrumentation for Gamma-Ray Spectroscopy

Söderström, Pär-Anders January 2011 (has links)
Neutron-rich rare-earth nuclei are among the most collective nuclei that can be found in nature. In particular, the doubly mid-shell nucleus 170Dy is expected to be the nucleus where the collective structure is maximized. This has implications for the astrophysical r-process, since it has been suggested that the collectivity maximum plays an important role in the abundances of the rare-earth elements that are created in supernova explosions. In this work, the collective structure of the five nuclei 168,170Dy and 167,168,169Ho are studied and different theoretical models are used to interpret the evolution of collectivity around the mid-shell. In order to produce and study even more neutron-rich nuclei in this mass region, new radioactive ion beam facilities will be a valuable tool. These facilities, however, require advanced instruments to study the weak signals of exotic nuclei in a high background environment. Two of these instruments are the γ-ray tracking spectrometer AGATA and the neutron detector array NEDA. For AGATA to work satisfactorily, the interaction position of the gamma rays must be determined with an accuracy of at least five millimetres. The position resolution is measured in this work using a model independent method based on the Doppler correction capabilities of the detector at two different distances between the detector and the source. For NEDA, one of the critical parameters is its ability to discriminate between neutrons and γ rays. By using digital electronics it is possible to employ advanced and efficient algorithms for pulse-shape discrimination. In this work, digital versions of the common analogue methods are shownto give as good, or better, results compared to the ones obtained using analogue electronics. Another method which effectively distinguishes between neutrons and γ rays is based on artificial neural networks. This method is also investigated in this work and is shown to yield even better results.
9

Essais sur les modèles collectifs avec production domestique / Essays on collective models with household production

Matteazzi, Eleonora 13 December 2010 (has links)
Ma thèse de doctorat a comme objectif de contribuer d'un point de vue théorique et empirique à la littérature sur les modèles collectifs avec production domestique. On veut montrer que les modèles collectifs représentent un instrument alternatif aux modèles unitaires de représentation du comportement individuel. Les modèles collectifs peuvent être utilise pour analyser la distribution des ressources au sein du ménage et pour évaluer le pouvoir de négociation de l'homme et de la femme. Ce dernier a des effets sur l'offre de travail, sur la consommation et sur le bien-être des individus dans le ménage. Dans les deux premiers chapitres, en utilisant les données de l'American Time Use Survey, on veut estimer les offres de travail de marché de l'homme et de la femme. Dans le première on se concentre sur la question de l'identification de la règle de partage lorsque il n'y a pas des facteurs de distribution observés. Dans le deuxième travail on prend en compte les solutions en coins. Dans les troisième et le quatrième chapitre on veut étendre les modèles sur les ménages agricoles du pays en voie de développement à l'approche collective. Dans le premier travail on se concentre sur la propriété de séparabilité du model lorsque les individus du ménage sont engagés dans la production d'un bien non-marchand et peuvent ne pas travailler sur le marché. Dans le deuxième on conduise des simulations en utilisant des données italienne. / The objective of this research project is to contribute from both a theoretical and empirical perspective to the literature about collective models of household behavior accounting for household production. In particular, the aim is to show that the collective models represent an alternative tool with respect to unitary models of household behavior with the advantage to allow the analysis of intra-household distribution of resources. This has some effects on individual labor supply, consumption and material well-being. In the first two chapters, using the American Time Use Survey, the objective is to estimate man and woman's market labor supply. In the first work we prove a new identification result of the sharing rule for the case where no distribution factor is observable. The second work develops a theoretical model of labor supply with domestic production that is consistent with corner solutions. In the third and fourth chapter the objective is to extend the farm-household literature to the collective approach. In the first work we focus on the separability property on the model when both the price of the domestic produced good and the price of individual time are endogenously determined within the household. We present some statics comparative results. In the second work, using Italian ISMEA data, we carry out a simulation.
10

Income shocks, household job search and labor supply / Choques de renda, procura familiar por emprego e oferta de trabalho

Solange Ledi Gonçalves 07 June 2017 (has links)
Analyses about aggregate employment, unemployment, and inactivity rates frequently disregard labor market trends of specific household members, which may explain some puzzles in the relationship between economic activity and labor market participation. The relevance of family approaches of labor supply transcends the aggregate macroeconomic trends and addresses important micro-level analysis concerning the behavior and intrahousehold decisions of members and policy-relevant results. Despite the consensus about the joint labor supply decisions of household members, studies are typically at the individual level and disregard sons and daughters as decision-makers in a family. Therefore, in this thesis, we investigate these questions for Brazil, in two studies. In the first study, we analyze the labor supply decisions of sons daughters aged 14 to 24 years living with their parents, in a reduced form exercise. We collaborate to the empirical literature about intrahousehold impacts of policies, testing whether the minimum wage, which affects the income of parents, impacts the final labor supply decisions of sons and daughters. We also verify if the policy has distinct effects depending on whether the eligible person is the father or the mother, aiming to test the income-pooling hypothesis. Our identification strategy is based on an intention-to-treat approach, and in a differences-in-differences estimator. Another innovation is the use of the PNADC (IBGE) for 2012-2016. We find that the direction and magnitude of the minimum wage effects affecting fathers and mothers, on the labor supply of sons and daughters, depend on who is and how many eligible members there exist in the household: it is negative, whether the eligible person is the mother or the father, and it is positive, whether both are eligible. Therefore, our results strengthen the argument in favor of household approaches, since the income pooling hypothesis does not seem to be valid in this context. In the second study, we investigate how the decisions about labor supply could determine the aggregate results of unemployment and inactivity of the secondary household earners. We develop and estimate a structural household job search model with on-the-job search. We extend Dey and Flinn (2008) to allow for unemployment and inactivity of mothers and sons and daughters who are subject to shocks to their employment and income shocks to fathers. These shocks may determine different search behavior and job acceptance, depending on the other household member\'s labor market situation. The model is estimated using the PME (IBGE) for 2004-2014. We perform counterfactual simulations, and we verify that the decreasing unemployment rate of sons/daughters would not have changed between 2004 and 2014 if the labor market opportunities and conditions of this member remain the same. The unemployment rate of mothers does not alter a lot in this period. The increasing trend in the inactivity of sons/daughters is mostly determined by a decreasing encouragement rate and the increasing dropout rate observed among these members in this period. These exogenous factors that determine the move to or the permanence in the inactivity could be related to the lower cost of education. We conclude that the use of individual job search models to understand aggregate unemployment and inactivity can be misleading, since the household search behavior matters in the labor supply decisions of secondary household earners. / As análises sobre taxas agregadas de emprego, desemprego e inatividade frequentemente ignoram a dinâmica dos membros das famílias no mercado de trabalho, a qual pode explicar puzzles na relação entre atividade econômica e participação no mercado de trabalho. A relevância das abordagens familiares para a oferta de trabalho está nas análises macroeconômicas sobre tendências agregadas, e também em análises microeconômicas do comportamento, decisões intrafamiliares e resultados de políticas. Apesar do consenso sobre as decisões conjuntas de oferta de trabalho dos membros da família, grande parte dos estudos são abordagens individuais e desconsideram filhos jovens como tomadores de decisão. Nesta tese, organizada em dois estudos, investigamos essas questões para o Brasil. No primeiro estudo, analisamos a decisão de ofertar trabalho de jovens entre 14 e 24 anos vivendo com os pais, em um exercício de forma reduzida. A tese colabora com a literatura empírica sobre os efeitos intrafamiliares de políticas, ao testar se o salário mínimo que afeta a renda dos pais impacta a decisão final dos filhos de ofertar trabalho. Também testamos a hipótese de agregação da renda, ao verificar se se a política tem efeitos distintos caso a pessoa elegível na família seja a mãe ou o pai. A estratégia de identificação é baseada em uma abordagem de intention-to-treat, e no uso do estimador de diferenças-em-diferenças. Outra inovação é o uso da PNADC (IBGE) para 2012-2016. Verificamos que a direção e a magnitude dos efeitos do salário mínimo dos pais, na oferta de trabalho dos filhos, dependem de quem é e de quantos são os membros elegíveis na família: o efeito é negativo, se a pessoa elegível é a mãe ou o pai, e é positivo, se ambos são elegíveis. Esses resultados reforçam o argumento em favor das abordagens intrafamiliares, uma vez que a hipótese de income-pooling não parece ser válida neste contexto. No segundo estudo, investigamos como as decisões de oferta de trabalho poderiam determinar os resultados agregados de desemprego e inatividade dos membros secundários. Desenvolvemos e estimamos um modelo estrutural de busca por emprego familiar com on-the-jobsearch. Estendemos o modelo de Dey e Flinn (2008), para permitir desemprego e inatividade de mães e filhos, sujeitos a choques em seus empregos e choques na renda dos pais. Esses choques podem determinar diferentes comportamentos de busca e aceitação de emprego, dependendo da situação do outro membro no mercado de trabalho. O modelo é estimado com a PME (IBGE) para 2004-2014. Realizamos simulações contrafactuais e verificamos que a taxa de desemprego dos filhos, decrescente entre 2004 e 2014, não teria se alterado no período, caso as condições e oportunidades de mercado de trabalho dos filhos tivessem continuado as mesmas de 2004. Já a taxa de desemprego das mães não sofre grandes alterações no período. A tendência crescente na inatividade dos filhos é determinada por uma taxa de encorajamento decrescente e uma taxa de desistência crescente, que refletem fatores exógenos que levam jovens trabalhadores à inatividade. Esses fatores exógenos podem estar relacionados ao menor custo da educação no período. Concluímos que o uso de modelos individuais de busca por emprego para entender o desemprego e a inatividade agregados deve ser desencorajado, pois o comportamento de busca familiar importa para as decisões de oferta de trabalho dos membros secundários da família.

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