This thesis investigates the role of classmates in the academic achievement of an individual student. I propose a new strategy to identify ability spillovers and combine this strategy with a unique data set to estimate peer effects in education. Using this innovative approach, I quantify the average effect of peers on own academic achievement in middle school and analyze heterogeneity of own response to peers along ability and gender lines. In Chapter 1, I provide a comprehensive empirical analysis of linear-in-means model of peer interactions and estimate the effect of the average quality of peers on academic progress of six-graders in Ontario public schools. I provide convincing evidence of the validity of my identification strategy and show that the average quality of classmates measured by their lagged test scores matters for individual academic achievement. I find positive, large and significant ability spillovers from peers in the same classroom. To reconcile the broad spectrum of peer effect's estimates in the literature, I also investigate the impact of peers in the same school and grade. I show that once a peer group is aggregated to a grade or class level, the effect attenuates towards zero. In Chapter 2, I relax the main assumption of linear-in-means model and compare alternative models of peer interactions with the empirical results from the first chapter. My findings imply that all students unambiguously benefit from the presence of high achieving peers. At the same time, academic progress of high-achievers does not suffer from the presence of low-achieving classmates. This finding provides important policy implications for ability grouping of students in schools. With the help of a policy experiment I demonstrate that spreading out high ability students across classrooms is an efficient strategy to increase the achievement level of every student. In the third chapter, I introduce gender dimension into the analysis of peer effects and investigate the role of class gender composition on individual academic achievement. I employ two different identification strategies and find that large share of girls in a class facilitates academic progress of both boys and girls. While he average quality of girls is one of the determinants of own achievement, peer-to-peer interactions and improved discipline in a classroom, when more girls are present, also play an important role.

This thesis investigates the role of classmates in the academic achievement of an individual student. I propose a new strategy to identify ability spillovers and combine this strategy with a unique data set to estimate peer effects in education. Using this innovative approach, I quantify the average effect of peers on own academic achievement in middle school and analyze heterogeneity of own response to peers along ability and gender lines. In Chapter 1, I provide a comprehensive empirical analysis of linear-in-means model of peer interactions and estimate the effect of the average quality of peers on academic progress of six-graders in Ontario public schools. I provide convincing evidence of the validity of my identification strategy and show that the average quality of classmates measured by their lagged test scores matters for individual academic achievement. I find positive, large and significant ability spillovers from peers in the same classroom. To reconcile the broad spectrum of peer effect's estimates in the literature, I also investigate the impact of peers in the same school and grade. I show that once a peer group is aggregated to a grade or class level, the effect attenuates towards zero. In Chapter 2, I relax the main assumption of linear-in-means model and compare alternative models of peer interactions with the empirical results from the first chapter. My findings imply that all students unambiguously benefit from the presence of high achieving peers. At the same time, academic progress of high-achievers does not suffer from the presence of low-achieving classmates. This finding provides important policy implications for ability grouping of students in schools. With the help of a policy experiment I demonstrate that spreading out high ability students across classrooms is an efficient strategy to increase the achievement level of every student. In the third chapter, I introduce gender dimension into the analysis of peer effects and investigate the role of class gender composition on individual academic achievement. I employ two different identification strategies and find that large share of girls in a class facilitates academic progress of both boys and girls. While he average quality of girls is one of the determinants of own achievement, peer-to-peer interactions and improved discipline in a classroom, when more girls are present, also play an important role.

This doctoral thesis consists of 4 self-contained chapters, bound together by their focus on household behavior and social interaction: Bargaining over Risk: The Impact of Decision Power on Household Portfolios. This paper provides an analysis of the internal financial decision-making process of households, employing a unique panel of household finances of the entire Swedish population. Exploitation of a source of exogenous variation in sex-specific labor demand reveals that the distribution of decision power among spouses is a driving force behind the aggregation of spouses’ preferences on financial decision making. Peer Effects and Academic Achievement: Regression Discontinuity Approach. The estimation of peer effects in schools has received much attention in recent years but convincing estimates are hard to produce due to self-selection. This paper overcomes this problem by employing a regression discontinuity design where student assignment into high-ability classes constitutes the source of identifying information. Domestic Equality and Marital Stability: Does More Equal Sharing of Childcare affect Divorce Risk? There is an unanimity that divorce wreaks havoc upon families in which it occurs and individuals growing up in a one-parent family are more likely to deal with term economic and social difficulties. Identifying means by which divorces can be reduced is therefore an important task from a public policy perspective and this paper investigates whether more equal sharing of childcare is successful in doing so. Do Classroom Peers Matter in an Early Tracking System? The potential for peers to affect educational achievement of students is central to many important policy debates, for instance on the impacts of ability tracking. Whether tracking affects efficiency and equality of opportunities depends on how peers enter the educational production function and this paper provides estimates of this. / <p>Diss. Stockholm : Handelshögskolan, 2014. Sammanfattning jämte 4 uppsatser</p>

A lo largo de los ultimos diez años los economistas hemos reconocido que en muchos casos las decisiones individuales se ven afectadas por las decisiones, los comportamientos las preferencias de otros agentes no solamente atraves del mercado sino tambien directamente por imitacion o aprendimiento, por el desarrollo de reglas sociales compartidas, por la difusion de informacion. Muchos estudios han estudiado estos mecanismos en varios contextos. Entre otros destacan la educacion, el mercado laboral, la criminalidad, las habitudines sanitarias. La relevancia de estos efectos de neighborhood es positiva y normativa a la vez. Por un lado, su existencia contribuye a la comprension de la extrema variabilidad de algunos fenomenos economicos entre grupos de individuos aparentemente homogeneos. Por otro lado, su existencia es una componente fundamental para el desarollo de intervenciones eficientes por parte del policy maker. Los estudios de la tesis analizan estos efectos en el contexto de las decisiones esscolares y en el mercado laboral. En el primer capitulo se muestra como la decision y el exito en completar la educacion segundaria por parte de los varones adolescentes afecta positivamente la de las mujeres de la misma edad residentes en las mismas ciudades. La muestra campionaria utilizada permite conlcuir que la correlacion entre los exitos de los varones y de las mujeres corresponde de hecho a una relacion causal entre las dos variables. Se concluye que cualquier intervencion que consiga aumentar la probabilidad de completar los estudios segundarios de los varones del uno por ciento tendrà como consequencia tambien un aumento de la probabilidad de las mujeres adolescentes de completar estos estudios entre 0.6 y 0.7 por ciento. En el segundo capitulo se evaluan los efectos sobre la durada del paro de pertenecer a un grupo social mas amplio.

Dans un monde où les réseaux deviennent une forme dominante d’organisation, la structure des réseaux et la position des individus en leur sein affectent les comportements individuels et les résultats économiques agrégés. L’analyse de la formation des réseaux par un planificateur central ou par les individus est au cœur de cette thèse en économie des réseaux. Le Chapitre 1 étudie de manière théorique la formation et la protection optimale des réseaux par un planificateur central sachant qu’un agent externe peut détruire k liens. La protection s’effectue soit en densifiant les liens entre les nœuds, soit en protégeant les liens. Lorsque le coût de protection est suffisamment faible, un réseau minimalement connecté constitué de liens protégés garantit le flux de communication; si ce coût est élevé, la solution optimale est de former un réseau symétrique où chaque nœud possède au moins k+1 liens non-protégés. Le Chapitre 2 explore la formation décentralisée de réseaux en laboratoire en analysant les décisions individuelles de formation de liens lorsqu’un agent a une valeur supérieure aux autres et que le processus de formation de liens est séquentiel. Les résultats montrent que la séquentialité facilite la coordination sur des réseaux efficaces mais qui ne correspondent pas à l’équilibre parfait en sous-jeu. L’hétérogénéité entre les agents accroit l’asymétrie du réseau en raison de la polarisation des liens sur l’agent à valeur supérieure. Le Chapitre 3 étudie l’impact de la formation endogène d’un réseau sur l’importance des effets de pairs, avec une application aux comportements malhonnêtes. Afin d’identifier les effets des comparaisons sociales, deux environnements contrôlés sont créés en laboratoire dans lesquels les individus choisissent ou non leurs pairs, puis observent leur comportement. Les résultats montrent que les effets de pairs sur les comportements malhonnêtes sont significativement accrus lorsque les individus peuvent choisir leurs pairs. / In a world where networks become a dominant form of organization, the structure of networks and the position of individuals in these networks affect individual behavior and aggregate economic outcomes. The analysis of network formation by a central planner or by individuals themselves is at the heart of this thesis on the economics of networks.Chapter 1 theoretically studies the optimal formation and protection of networks by a central planner knowing that an external agent can destroy k links. The protection of the network can be guaranteed either by densifying the links between nodes, or by protecting the links. When the cost of protection is relatively small, a minimally connected network composed of protected links guarantees the communication flow; if this cost is high, the optimal solution is to form a symmetric network where each node has at least k+1 non-protected links.Chapter 2 explores the decentralized formation of networks in the laboratory by analyzing individual linking formation decisions when one agent has a higher value than others and that the linking formation process is sequential. The results show that sequentiality facilitatesthe coordination on efficient networks but that do not correspond to the Subgame PerfectEquilibrium. The heterogeneity across agents increases the asymmetry of networks because of the polarization of links on the agent with a higher value.Chapter 3 studies the impact of the endogenous formation of networks on the importance of peer effects, applied to dishonest behavior. In order to identify the effects of social comparisons, two controlled environments are designed in the laboratory in which individuals choose or not their peers, and then observe their behavior. The results show that peer effects on dishonest behavior are significantly higher when individuals can choose their peers.

O objetivo desta pesquisa é analisar o papel do gênero no aprendizado escolar no Brasil, enfatizando desigualdades e o efeito de pares. Essas questões foram analisadas em cinco capítulos, incluindo a introdução e as considerações finais. Inicia-se com uma breve descrição sobre a desigualdade de gênero em termos de aprendizado de matemática e português no Brasil considerando, principalmente, os alunos de 5º e 9º ano. Observa-se que os meninos tendem a se sair melhor em matemática que as meninas, uma relação que se inverte para português e, ainda, que estas desigualdades aumentam nos anos escolares mais avançados. O segundo capítulo visa investigar os fatores associados a estas diferenças, explorando características dos alunos, professores e escolas através de dois métodos diferentes de decomposição, uma que explora a diferença de média dos resultados e outra que analisa toda a distribuição de notas. Os resultados indicam que apesar de meninos e meninas possuírem características de contexto socioeconômico e familiares parecidas, o principal fator contribuinte para as diferenças de aprendizado está no retorno destas características em termos de nota para cada um dos dois gêneros, o que, portanto, reduz o papel do professor e da escola na diminuição destas desigualdades. O terceiro capítulo trata do efeito de pares no aprendizado do 5º ano das escolas públicas brasileiras. Ele investiga, de maneira causal, a relação entre a proporção de meninas na escola e o aprendizado. Identifica-se uma relação positiva entre notas e a proporção de meninas em português e, principalmente, em matemática, uma disciplina cujas meninas tendem a se sair piores do que os meninos. Isto, portanto, chama atenção para o tópico do quarto capítulo, que busca elucidar mecanismos por trás desta influência. Verifica-se, portanto, que o efeito positivo das meninas ocorre via comportamento, o que se reflete em menor violência, maior expectativa dos professores sobre o futuro escolar dos alunos e facilita o andamento da classe. Diante disso, em termos de políticas públicas, o trabalho chama atenção para o gênero como fator importante na alocação de alunos e professores dentro da escola. Assim, levar os resultados aqui apresentados em consideração na formulação e execução de políticas pode resultar em medidas efetivas e de baixo custo voltadas para o aumento do aprendizado escolar. / The aim of this research is to analyze the role of gender on scholastic achievement in Brazil, emphasizing inequalities and peer effects. These issues are analyzed in five chapters, including the introduction and the concluding remarks. We start by briefly describing gender inequality in terms of math and literacy achievements in Brazil, focusing, mainly, on 5th and 9th grade students. We observe that boys tend to outperform girls in math, a relation that reverses in literacy and, furthermore, that these inequalities increase in more advanced schooling years. The second chapter aims to investigate the factors associated with these differences, exploring students’, teachers’ and schools characteristics in two different types of decomposition methods, one that explores differences in mean achievement and another that assesses the entire test score distribution. The results indicate that despite boys and girls having similar family and socioeconomic characteristics, the main contributor towards the learning differences is the return of these characteristics in terms of test scores for each of the two genders, which, therefore, reduces the role of teachers’ and schools in diminishing these inequalities. The third chapter deals with peer effects in 5th grade Brazilian public schools. It investigates the casual relationship between the proportion of girls at school and learning. We identify a positive relation between test scores and the proportion of girls in literacy and, mainly, in math, a subject that girls tend to be outscored by boys. This, in fact, draws attention to the fourth chapter, which seeks to elucidate the mechanisms behind this influence. We verify that the benefits of having a greater proportion of girls are mainly through improvements in student behavior, which reflects in less violence, greater teacher expectations over the student’s academic future, and facilitates classroom progress. In terms of public policies, this research draws attention to gender as an important factor in the allocation of students and teachers within schools. Therefore, the consideration of our findings in the formulation and execution of policies can result in effective and low cost measures aimed at increasing scholastic achievement.

This dissertation consists of three chapters that study social influence and the diffusion of information in decision making contexts with limited observable outcomes. Chapter 1 studies social interactions and female genital mutilation (FGM), a traditional procedure of removing the whole or part of the female genitalia for non-medical reasons. Using survey data from Egypt, this paper attempts to identify effects of peer adoption and medicalization on a household's decision to opt for FGM. We find that households are less likely to adopt if their peers adopt less and (in certain areas) if medicalization is more widely used by their peers. Chapter 2, using a lab experiment, studies how influence of any given agent in a social network is driven by assessments of their reliability by network members based on observations of their past behavior. Agents repeatedly make choices, the optimality of which depends on an unobserved state of the world; they are able to communicate those choices with their social peers; and earn a reward after the last period. We enrich the non-Bayesian DeGroot model by postulating that the extent to which network members are influenced by a peer member depends on the extent of nonconformity, variability and extremeness of their past choices. We find that inferred reliability has an effect as significant as network centrality on social influence; when weighting the views of their peers, individuals are sensitive to their observed behavior, especially for those peers with low centrality. Chapter 3 analyzes the effects of a large-scale randomized intervention which provided incentivized block grants with the aim of improving twelve health and education outcomes. Communities were incentivized by having grants sizes dependent on performance. Our goal is to refine an earlier intention-to-treat evaluation, by examining the intervention's heterogeneous effect on the different subpopulations of households defined by their participation in health information outreach. We find that incentivized grants have a strong effect on immunization rates of children from households participating in outreach activities: as high as a 14.3% increase for children aged six months or less, compared to a maximum average treatment effect of 3.7%.

O objetivo desta pesquisa é analisar o papel do gênero no aprendizado escolar no Brasil, enfatizando desigualdades e o efeito de pares. Essas questões foram analisadas em cinco capítulos, incluindo a introdução e as considerações finais. Inicia-se com uma breve descrição sobre a desigualdade de gênero em termos de aprendizado de matemática e português no Brasil considerando, principalmente, os alunos de 5º e 9º ano. Observa-se que os meninos tendem a se sair melhor em matemática que as meninas, uma relação que se inverte para português e, ainda, que estas desigualdades aumentam nos anos escolares mais avançados. O segundo capítulo visa investigar os fatores associados a estas diferenças, explorando características dos alunos, professores e escolas através de dois métodos diferentes de decomposição, uma que explora a diferença de média dos resultados e outra que analisa toda a distribuição de notas. Os resultados indicam que apesar de meninos e meninas possuírem características de contexto socioeconômico e familiares parecidas, o principal fator contribuinte para as diferenças de aprendizado está no retorno destas características em termos de nota para cada um dos dois gêneros, o que, portanto, reduz o papel do professor e da escola na diminuição destas desigualdades. O terceiro capítulo trata do efeito de pares no aprendizado do 5º ano das escolas públicas brasileiras. Ele investiga, de maneira causal, a relação entre a proporção de meninas na escola e o aprendizado. Identifica-se uma relação positiva entre notas e a proporção de meninas em português e, principalmente, em matemática, uma disciplina cujas meninas tendem a se sair piores do que os meninos. Isto, portanto, chama atenção para o tópico do quarto capítulo, que busca elucidar mecanismos por trás desta influência. Verifica-se, portanto, que o efeito positivo das meninas ocorre via comportamento, o que se reflete em menor violência, maior expectativa dos professores sobre o futuro escolar dos alunos e facilita o andamento da classe. Diante disso, em termos de políticas públicas, o trabalho chama atenção para o gênero como fator importante na alocação de alunos e professores dentro da escola. Assim, levar os resultados aqui apresentados em consideração na formulação e execução de políticas pode resultar em medidas efetivas e de baixo custo voltadas para o aumento do aprendizado escolar. / The aim of this research is to analyze the role of gender on scholastic achievement in Brazil, emphasizing inequalities and peer effects. These issues are analyzed in five chapters, including the introduction and the concluding remarks. We start by briefly describing gender inequality in terms of math and literacy achievements in Brazil, focusing, mainly, on 5th and 9th grade students. We observe that boys tend to outperform girls in math, a relation that reverses in literacy and, furthermore, that these inequalities increase in more advanced schooling years. The second chapter aims to investigate the factors associated with these differences, exploring students’, teachers’ and schools characteristics in two different types of decomposition methods, one that explores differences in mean achievement and another that assesses the entire test score distribution. The results indicate that despite boys and girls having similar family and socioeconomic characteristics, the main contributor towards the learning differences is the return of these characteristics in terms of test scores for each of the two genders, which, therefore, reduces the role of teachers’ and schools in diminishing these inequalities. The third chapter deals with peer effects in 5th grade Brazilian public schools. It investigates the casual relationship between the proportion of girls at school and learning. We identify a positive relation between test scores and the proportion of girls in literacy and, mainly, in math, a subject that girls tend to be outscored by boys. This, in fact, draws attention to the fourth chapter, which seeks to elucidate the mechanisms behind this influence. We verify that the benefits of having a greater proportion of girls are mainly through improvements in student behavior, which reflects in less violence, greater teacher expectations over the student’s academic future, and facilitates classroom progress. In terms of public policies, this research draws attention to gender as an important factor in the allocation of students and teachers within schools. Therefore, the consideration of our findings in the formulation and execution of policies can result in effective and low cost measures aimed at increasing scholastic achievement.

Research in retirement planning has found that people are delaying investing in a retirement plan and are missing out on thousands of potential savings from not investing since 401(k)’s are protected against income taxes. This delay of investment could be occurring as a result of choice overload. The current study examined choice overload in the financial context of 401(k) retirement plans in order to find an efficient solution. Social influences and peer effects have been shown to increase retirement plan participation rates. Participants (n=119) were randomly assigned to a control condition or one of two social preferences conditions, one of which had a heavily skewed social preference while the other had relatively equal preferences. Participants were instructed to build a 401(k) and then were asked questions regarding their financial literacy and overload and satisfaction with their decisions. There was no significant effect of social preferences on overload or satisfaction. However, financial literacy was found to be a negative predictor of satisfaction.

abstract: <bold>your words</bold> / Dissertation/Thesis / Masters Thesis Agribusiness 2014