Estimating the need and supply of hired seasonal farm workers, Baldwin County, Alabama.

"April 1955."

Three essays on labor liberalization and its effects on world economy

This dissertation consists of three theoretical essays on immigration, international trade and political economy. The first two essays analyze the political economy of immigration in developed countries. The third essay explores new ground on the effects of labor liberalization in developing countries. Trade economists have witnessed remarkable methodological developments in mathematical and game theoretical models during the last seventy years. This dissertation benefits from these advances to analyze economic issues related to immigration. The first essay applies a long run general equilibrium trade model similar to Krugman (1980), and blends it with the median voter ala-Mayer (1984) framework. The second essay uses a short run general equilibrium specific factor trade model similar to Jones (1975) and incorporates it with the median voter model similar to Benhabib (1997). The third essay employs a five stage game theoretical approach similar to Vogel (2007) and solves it by the method of backward induction. The first essay shows that labor liberalization is more likely to come about in societies that have more taste for varieties, and that workers and capital owners could share the same positive stance toward labor liberalization. In a dynamic model, it demonstrates that the median voter is willing to accept fewer immigrants in the first period in order to preserve her domestic political influence in the second period threatened by the naturalization of these immigrants. The second essay shows that the liberalization of labor depends on the host country's stock and distribution of capital, and the number of groups of skilled workers within each country. I demonstrate that the more types of goods both countries produce, the more liberal the host country is toward immigration. The third essay proposes a theory of free movement of goods and labor between two economies with imperfect labor contracts. The heart of my analysis lies in the determinants of talent development where individuals' decisions to emigrate are related to the fixed costs of emigration. Finally, free trade and labor affect income via an indirect effect on individuals' incentives to invest in the skill levels and a direct effect on the prices of goods.

Essays on the Economics of Higher Education

At least since the seminal works of Jacob Mincer, labor economists have sought to understand how students make higher education investment decisions. Mincer’s original work seeks to understand how students decide how much education to accrue; subsequent work by various authors seeks to understand how students choose where to attend college, what field to major in, and whether to drop out of college.

Broadly speaking, this rich sub-field of literature contributes to society in two ways: First, it provides a better understanding of important social behaviors. Second, it helps policymakers anticipate the responses of students when evaluating various policy reforms.

While research on the higher education investment decisions of students has had an enormous impact on our understanding of society and has shaped countless education policies, students are only one interested party in the higher education landscape. In the jargon of economists, students represent only the `demand side’ of higher education---customers who are choosing options from a set of available alternatives. Opposite students are instructors and administrators who represent the `supply side’ of higher education---those who decide which options are available to students.

For similar reasons, it is also important to understand how individuals on the supply side of education make decisions: First, this provides a deeper understanding of the behaviors of important social institutions. Second, it helps policymakers anticipate the responses of instructors and administrators when evaluating various reforms. However, while there is substantial literature understanding decisions made on the demand side of education, there is far less attention paid to decisions on the supply side of education.

This dissertation uses empirical evidence to better understand how instructors and administrators make decisions and the implications of these decisions for students.

In the first chapter, I use data from Duke University and a Bayesian model of correlated learning to measure the signal quality of grades across academic fields. The correlated feature of the model allows grades in one academic field to signal ability in all other fields allowing me to measure both ‘own category' signal quality and ‘spillover' signal quality. Estimates reveal a clear division between information rich Science, Engineering, and Economics grades and less informative Humanities and Social Science grades. In many specifications, information spillovers are so powerful that precise Science, Engineering, and Economics grades are more informative about Humanities and Social Science abilities than Humanities and Social Science grades. This suggests students who take engineering courses during their Freshman year make more informed specialization decisions later in college.

In the second chapter, I use data from the University of Central Arkansas to understand how universities decide which courses to offer and how much to spend on instructors for these courses. Course offerings and instructor characteristics directly affect the courses students choose and the value they receive from these choices. This chapter reveals the university preferences over these student outcomes which best explain observed course offerings and instructors. This allows me to assess whether university incentives are aligned with students, to determine what alternative university choices would be preferred by students, and to illustrate how a revenue neutral tax/subsidy policy can induce a university to make these student-best decisions.

In the third chapter, co-authored with Thomas Ahn, Peter Arcidiacono, and Amy Hopson, we use data from the University of Kentucky to understand how instructors choose grading policies. In this chapter, we estimate an equilibrium model in which instructors choose grading policies and students choose courses and study effort given grading policies. In this model, instructors set both a grading intercept and a return on ability and effort. This builds a rich link between the grading policy decisions of instructors and the course choices of students. We use estimates of this model to infer what preference parameters best explain why instructors chose estimated grading policies. To illustrate the importance of these supply side decisions, we show changing grading policies can substantially reduce the gender gap in STEM enrollment.

Essays on Job Search and Labor Market Dynamics

This dissertation consists of three separate essays on job search and labor market dynamics. In the first essay, “The Impact of Labor Market Conditions on Job Creation: Evidence from Firm Level Data”, I study how much changes in labor market conditions reduce employment fluctuations over the business cycle. Changes in labor market conditions make hiring more expensive during expansions and cheaper during recessions, creating counter-cyclical incentives for job creation. I estimate firm level elasticities of labor demand with respect to changes in labor market conditions, considering two margins: changes in labor market tightness and changes in wages. Using employer-employee matched data from Brazil, I find that all firms are more sensitive to changes in wages rather than labor market tightness, and there is substantial heterogeneity in labor demand elasticity across regions. Based on these results, I demonstrate that changes in labor market conditions reduce the variance of employment growth over the business cycle by 20% in a median region, and this effect is equally driven by changes along each margin. Moreover, I show that the magnitude of the effect of labor market conditions on employment growth can be significantly affected by economic policy. In particular, I document that the rapid growth of the national minimum wages in Brazil in 1997-2010 amplified the impact of the change in labor market conditions during local expansions and diminished this impact during local recessions.

In the second essay, “A Framework for Estimating Persistence of Local Labor

Demand Shocks”, I propose a decomposition which allows me to study the persistence of local labor demand shocks. Persistence of labor demand shocks varies across industries, and the incidence of shocks in a region depends on the regional industrial composition. As a result, less diverse regions are more likely to experience deeper shocks, but not necessarily more long lasting shocks. Building on this idea, I propose a decomposition of local labor demand shocks into idiosyncratic location shocks and nationwide industry shocks and estimate the variance and the persistence of these shocks using the Quarterly Census of Employment and Wages (QCEW) in 1990-2013.

In the third essay, “Conditional Choice Probability Estimation of Continuous- Time Job Search Models”, co-authored with Peter Arcidiacono and Arnaud Maurel, we propose a novel, computationally feasible method of estimating non-stationary job search models. Non-stationary job search models arise in many applications, where policy change can be anticipated by the workers. The most prominent example of such policy is the expiration of unemployment benefits. However, estimating these models still poses a considerable computational challenge, because of the need to solve a differential equation numerically at each step of the optimization routine. We overcome this challenge by adopting conditional choice probability methods, widely used in dynamic discrete choice literature, to job search models and show how the hazard rate out of unemployment and the distribution of the accepted wages, which can be estimated in many datasets, can be used to infer the value of unemployment. We demonstrate how to apply our method by analyzing the effect of the unemployment benefit expiration on duration of unemployment using the data from the Survey of Income and Program Participation (SIPP) in 1996-2007.

Modelling and estimating models of physician labour supply and productivity

Ma thèse s’intéresse aux politiques de santé conçues pour encourager l’offre de services de santé. L’accessibilité aux services de santé est un problème majeur qui mine le système de santé de la plupart des pays industrialisés. Au Québec, le temps médian d’attente entre une recommandation du médecin généraliste et un rendez-vous avec un médecin spécialiste était de 7,3 semaines en 2012, contre 2,9 semaines en 1993, et ceci malgré l’augmentation du nombre de médecins sur cette même période. Pour les décideurs politiques observant l’augmentation du temps d’attente pour des soins de santé, il est important de comprendre la structure de l’offre de travail des médecins et comment celle-ci affecte l’offre des services de santé. Dans ce contexte, je considère deux principales politiques. En premier lieu, j’estime comment les médecins réagissent aux incitatifs monétaires et j’utilise les paramètres estimés pour examiner comment les politiques de compensation peuvent être utilisées pour déterminer l’offre de services de santé de court terme. En second lieu, j’examine comment la productivité des médecins est affectée par leur expérience, à travers le mécanisme du "learning-by-doing", et j’utilise les paramètres estimés pour trouver le nombre de médecins inexpérimentés que l’on doit recruter pour remplacer un médecin expérimenté qui va à la retraite afin de garder l’offre des services de santé constant. Ma thèse développe et applique des méthodes économique et statistique afin de mesurer la réaction des médecins face aux incitatifs monétaires et estimer leur profil de productivité (en mesurant la variation de la productivité des médecins tout le long de leur carrière) en utilisant à la fois des données de panel sur les médecins québécois, provenant d’enquêtes et de l’administration. Les données contiennent des informations sur l’offre de travail de chaque médecin, les différents types de services offerts ainsi que leurs prix. Ces données couvrent une période pendant laquelle le gouvernement du Québec a changé les prix relatifs des services de santé. J’ai utilisé une approche basée sur la modélisation pour développer et estimer un modèle structurel d’offre de travail en permettant au médecin d’être multitâche. Dans mon modèle les médecins choisissent le nombre d’heures travaillées ainsi que l’allocation de ces heures à travers les différents services offerts, de plus les prix des services leurs sont imposés par le gouvernement. Le modèle génère une équation de revenu qui dépend des heures travaillées et d’un indice de prix représentant le rendement marginal des heures travaillées lorsque celles-ci sont allouées de façon optimale à travers les différents services. L’indice de prix dépend des prix des services offerts et des paramètres de la technologie de production des services qui déterminent comment les médecins réagissent aux changements des prix relatifs. J’ai appliqué le modèle aux données de panel sur la rémunération des médecins au Québec fusionnées à celles sur l’utilisation du temps de ces mêmes médecins. J’utilise le modèle pour examiner deux dimensions de l’offre des services de santé. En premierlieu, j’analyse l’utilisation des incitatifs monétaires pour amener les médecins à modifier leur production des différents services. Bien que les études antérieures ont souvent cherché à comparer le comportement des médecins à travers les différents systèmes de compensation,il y a relativement peu d’informations sur comment les médecins réagissent aux changementsdes prix des services de santé. Des débats actuels dans les milieux de politiques de santé au Canada se sont intéressés à l’importance des effets de revenu dans la détermination de la réponse des médecins face à l’augmentation des prix des services de santé. Mon travail contribue à alimenter ce débat en identifiant et en estimant les effets de substitution et de revenu résultant des changements des prix relatifs des services de santé. En second lieu, j’analyse comment l’expérience affecte la productivité des médecins. Cela a une importante implication sur le recrutement des médecins afin de satisfaire la demande croissante due à une population vieillissante, en particulier lorsque les médecins les plus expérimentés (les plus productifs) vont à la retraite. Dans le premier essai, j’ai estimé la fonction de revenu conditionnellement aux heures travaillées, en utilisant la méthode des variables instrumentales afin de contrôler pour une éventuelle endogeneité des heures travaillées. Comme instruments j’ai utilisé les variables indicatrices des âges des médecins, le taux marginal de taxation, le rendement sur le marché boursier, le carré et le cube de ce rendement. Je montre que cela donne la borne inférieure de l’élasticité-prix direct, permettant ainsi de tester si les médecins réagissent aux incitatifs monétaires. Les résultats montrent que les bornes inférieures des élasticités-prix de l’offre de services sont significativement positives, suggérant que les médecins répondent aux incitatifs. Un changement des prix relatifs conduit les médecins à allouer plus d’heures de travail au service dont le prix a augmenté. Dans le deuxième essai, j’estime le modèle en entier, de façon inconditionnelle aux heures travaillées, en analysant les variations des heures travaillées par les médecins, le volume des services offerts et le revenu des médecins. Pour ce faire, j’ai utilisé l’estimateur de la méthode des moments simulés. Les résultats montrent que les élasticités-prix direct de substitution sont élevées et significativement positives, représentant une tendance des médecins à accroitre le volume du service dont le prix a connu la plus forte augmentation. Les élasticitésprix croisées de substitution sont également élevées mais négatives. Par ailleurs, il existe un effet de revenu associé à l’augmentation des tarifs. J’ai utilisé les paramètres estimés du modèle structurel pour simuler une hausse générale de prix des services de 32%. Les résultats montrent que les médecins devraient réduire le nombre total d’heures travaillées (élasticité moyenne de -0,02) ainsi que les heures cliniques travaillées (élasticité moyenne de -0.07). Ils devraient aussi réduire le volume de services offerts (élasticité moyenne de -0.05). Troisièmement, j’ai exploité le lien naturel existant entre le revenu d’un médecin payé à l’acte et sa productivité afin d’établir le profil de productivité des médecins. Pour ce faire, j’ai modifié la spécification du modèle pour prendre en compte la relation entre la productivité d’un médecin et son expérience. J’estime l’équation de revenu en utilisant des données de panel asymétrique et en corrigeant le caractère non-aléatoire des observations manquantes à l’aide d’un modèle de sélection. Les résultats suggèrent que le profil de productivité est une fonction croissante et concave de l’expérience. Par ailleurs, ce profil est robuste à l’utilisation de l’expérience effective (la quantité de service produit) comme variable de contrôle et aussi à la suppression d’hypothèse paramétrique. De plus, si l’expérience du médecin augmente d’une année, il augmente la production de services de 1003 dollar CAN. J’ai utilisé les paramètres estimés du modèle pour calculer le ratio de remplacement : le nombre de médecins inexpérimentés qu’il faut pour remplacer un médecin expérimenté. Ce ratio de remplacement est de 1,2.

Supply Chain Adaptation of Finnish Companies in Chinese Institutional Environment

Within the last few decades of operations and supply chain management, the field has seen the rise of so called best practices, methods that will help supply chains obtain their business goals and gain a competitive edge. These methods were thought to be universal. This however is not always the case, as the surrounding business environment could have a significant impact on what will be effective in gaining competitive edge. Contingency theory states that the success of a supply chain is determined by both internal capabilities, as well as external context aligning. This creates a strategic fit, which is a major determinant of success. In order for supply chains to reach this strategic fit, they must adapt. As China has seen rapid growth and over the last few decades become one of the major economies of the world, Western companies have tried to establish themselves there, only to find that the Chinese market is extremely difficult to operate in. The aim of this thesis was to investigate from contingency theory perspective, what are the institutional factors that affect supply chain management of Finnish companies operating in China, and how do Finnish companies adapt their supply chains to better fit the Chinese institutional environment. A theoretical model was created for this thesis, in which supply chains possess resources, which can be combined in a meaningful manner to create capabilities. Both resources and capabilities are affected by the surrounding institutional environment, which forces supply chains to adapt in order to find a better strategic fit. A total of six Finnish managers from three large and three small companies operating in China were interviewed. The results indicated that the Chinese business environment is significantly different, than that of Finland or Western countries in general. Three institutional factors were identified: Confucian though, fast-paced business environment, and managing labor force. These three institutional factors made the relationship and delivery capabilities particularly important, as well as human resources, reputation, physical resources and technological resources. In conclusion, it was discovered that the Chinese institutional environment is heavily affected by Confucian thought, as well as the rapid market growth. These are the two most important institutional factors that shape the Chinese market. If supply chains wish to be successful in China, adaptation regarding these two institutional factors should yield good results.

Three essays in labor economics and applied econometrics

Méthodologie:Cadre conceptuel: Principal-agent

A NAIRU assessment: an applied case to Colombia’s labor markets

Given the discrepancy over the optimum levels of employment for Colombia, this research targets both, the national and urban, Non-Accelerating Inflation Rate of Unemployment (NAIRU) for the Colombian markets -- In doing so, there is a strong pertinence in estimating the constant NAIRU through raw and minimally altered data and providing the reader with a complete brief of the theory in which the model is founded -- The introduction of supply shocks is considered to attain improved estimations and a more reliable assessment of the NAIRU to those that have previously been attempted -- The backbone of the analysis is conducted through the relationship established by the Phillips curve from 2001 until 2015

Supply Chain Adaptation of Finnish Companies in Chinese Institutional Environment

Within the last few decades of operations and supply chain management, the field has seen the rise of so called best practices, methods that will help supply chains obtain their business goals and gain a competitive edge. These methods were thought to be universal. This however is not always the case, as the surrounding business environment could have a significant impact on what will be effective in gaining competitive edge. Contingency theory states that the success of a supply chain is determined by both internal capabilities, as well as external context aligning. This creates a strategic fit, which is a major determinant of success. In order for supply chains to reach this strategic fit, they must adapt. As China has seen rapid growth and over the last few decades become one of the major economies of the world, Western companies have tried to establish themselves there, only to find that the Chinese market is extremely difficult to operate in. The aim of this thesis was to investigate from contingency theory perspective, what are the institutional factors that affect supply chain management of Finnish companies operating in China, and how do Finnish companies adapt their supply chains to better fit the Chinese institutional environment. A theoretical model was created for this thesis, in which supply chains possess resources, which can be combined in a meaningful manner to create capabilities. Both resources and capabilities are affected by the surrounding institutional environment, which forces supply chains to adapt in order to find a better strategic fit. A total of six Finnish managers from three large and three small companies operating in China were interviewed. The results indicated that the Chinese business environment is significantly different, than that of Finland or Western countries in general. Three institutional factors were identified: Confucian though, fast-paced business environment, and managing labor force. These three institutional factors made the relationship and delivery capabilities particularly important, as well as human resources, reputation, physical resources and technological resources. In conclusion, it was discovered that the Chinese institutional environment is heavily affected by Confucian thought, as well as the rapid market growth. These are the two most important institutional factors that shape the Chinese market. If supply chains wish to be successful in China, adaptation regarding these two institutional factors should yield good results.

Studying the Causes and Consequences of Internal Labor Migration Using Survey and Administrative Data Sources

This dissertation comprises three chapters. The first chapter motivates the use of a novel data set combining survey and administrative sources for the study of internal labor migration. By following a sample of individuals from the American Community Survey (ACS) across their employment outcomes over time according to the Longitudinal Employer-Household Dynamics (LEHD) database, I construct a measure of geographic labor mobility that allows me to exploit information about individuals prior to their move. This enables me to explore aspects of the migration decision, such as homeownership and employment status, in ways that have not previously been possible. In the second chapter, I use this data set to test the theory that falling home prices affect a worker’s propensity to take a job in a different metropolitan area from where he is currently located. Employing a within-CBSA and time estimation that compares homeowners to renters in their propensities to relocate for jobs, I find that homeowners who have experienced declines in the nominal value of their homes are approximately 12% less likely than average to take a new job in a location outside of the metropolitan area where they currently reside. This evidence is consistent with the hypothesis that housing lock-in has contributed to the decline in labor mobility of homeowners during the recent housing bust. The third chapter focuses on a sample of unemployed workers in the same data set, in order to compare the unemployment durations of those who find subsequent employment by relocating to a new metropolitan area, versus those who find employment in their original location. Using an instrumental variables strategy to address the endogeneity of the migration decision, I find that out-migrating for a new job significantly reduces the time to re-employment. These results stand in contrast to OLS estimates, which suggest that those who move have longer unemployment durations. This implies that those who migrate for jobs in the data may be particularly disadvantaged in their ability to find employment, and thus have strong short-term incentives to relocate.

Beliefs And Misbeliefs About Current Interventions During Labor And Delivery In Brazil.

30 Suppl 1

O programa de incentivo à instalação de cozinhas comunitárias: avaliação de uma política pública brasileira

O trabalho tem como objetivo descrever e avaliar as Cozinhas Comunitárias (CC) apoiadas pelo Ministério do Desenvolvimento Social (MDS) em funcionamento no Brasil em 2006. Trata-se de estudo transversal que investigou as CC, com projetos contemplados nos editais do MDS realizados entre os anos de 2003 a 2005. Inicialmente foram identificadas as CC em funcionamento e estas CC foram visitadas para a coleta de dados relativos ao atendimento prestado, avaliação da estrutura física e das refeições oferecidas. A estrutura física foi avaliada por meio de um check-list, baseado nas exigências da legislação sanitária, e a oferta de refeições foi caracterizada pelos alimentos e preparações oferecidas pelas CC para determinar o valor nutricional das refeições. A maioria das cozinhas financiadas (60%) estava em fase de implementação no momento da entrevista, entre as cozinhas em funcionamento, a maioria estava localizada nos Estados de Santa Catarina e Paraná. Observou-se também que cerca de 20% das cozinhas não ofereciam refeições regularmente. Ao realizar a avaliação nutricional das refeições, foi observada uma grande heterogeneidade na oferta de alimentos. Ao avaliar as condições higiênico-sanitárias, quase a totalidade das CC foram classificadas como deficientes ou regulares, indicando inadequação na produção de refeições. O Programa das Cozinhas Comunitárias pode exercer importante papel nas políticas de segurança alimentar e nutricional do país, no entanto, devem ser realizados esforços no sentido de garantir a implantação em comunidades situadas nos Estados menos desenvolvidos, com fixação de números mínimos para atendimento, de parâmetros nutricionais e garantia de fornecimento seguro de alimentos

Queimadas nos canaviais e perspectivas dos cortadores de cana-de-açúcar em Macatuba, São Paulo

A lei nº 11.241/2002 do estado de São Paulo proíbe a queima de cana-de-açúcar pré-colheita devido ao alto impacto que a fumaça desse processo causa na saúde coletiva e no meio ambiente. De modo gradativo, a previsão inicial era de que a proibição fosse efetiva em 2031. Posteriormente, acordo entre governo do Estado e União da Indústria de Cana-de-açúcar (Unica), estabeleceu redução do prazo para 2017. A cana-de-açúcar, quando não queimada, exige muito mais esforço dos cortadores, diminuindo a produtividade do corte manual em comparação às máquinas colheitadeiras. A ausência das queimadas traz benefícios à saúde e ao meio ambiente, no entanto, pouco ainda se sabe a respeito das consequências da mecanização para a mão de obra rural nos canaviais. Este artigo busca analisar esse quadro de incerteza sobre o que ocorrerá do ponto de vista dos cortadores de cana e o reconhecimento das consequências da lei em suas vidas. Durante a safra de cana de 2006, foram aplicados questionários a 40 cortadores de cana, de diferentes idades e gênero, no bairro Jardim América, em Macatuba-SP, em suas casas ou na rua. Perguntas qualitativas e quantitativas que abordavam temas socioeconômicos, de saúde, reconhecimento da lei e perspectivas de trabalho. Os entrevistados apresentaram um dilema entre o ar limpo e a perspectiva de trabalho. Muitos se apresentaram indecisos e sem incentivos a trabalhar em outros setores, apesar de grande parte gostar do local onde vive e se interessar por continuar a trabalhar na agricultura

Effects of enriched colostrum supply in intestinal mucosa morphology of newborn calves

Colostrum intake in neonatal calves is essential to obtain passive immunity and to influence metabolism, endocrine systems and the nutritional state. This study compares morphologic features of small intestine of calves fed a colostrum second meal at 12 hours of life with concentrations of immunoglobulin G (IgG) higher than 100mg mL(-1) (fresh colostrum or artificially prepared with addition of lyophilized colostrum) or smaller than 30mg mL(-1). Twenty-four Holstein calves were randomly grouped according to concentration of IgG intake at 12 hours of life: low (less than 30mg mL(-1)); high (more than 100mg mL(-1)); plus lyophilized colostrum (more than 120mg mL(-1)). Intestinal tissue samples were collected at 0, 10, 24 and 72 hours after birth to evaluate morphology in segments: duodenum; proximal, middle and distal jejunum and ileum by examined with a scanning electron microscope. Villi of all segments showed more organized and uniform morphology characteristics with age. Only the animals fed colostrum with more than 100mg mL(-1) of IgG at 24 hours after birth still showed the distal jejunum villi disoriented and more united in comparison to the other ages and groups. Intake of lyophilized colostrum affected ileum morphology along experiment period. Higher concentration of immunologic and bioactive elements supplied for longer period of time could be responsible for promoting effects on the enterocytes. Use of colostrum with high IgG concentrations, with or without addition of lyophilized colostrum, influenced the precocity of the intestinal mucosa development in newborn calves, suggesting earlier maturation of the mucosa.

Do labor aos mitos: uma nova linha no mapa das pesquisas em Etnomatemática

In this paper we highlight the existence of a new line of research within the Ethnomathematics Program. In its origin, research in this area has sought to contribute to understanding regarding the diversity of mathematical thought through a careful look at work activities. In recent years, however, we have paid increasing attention to the affirmations of anthropologists that myths can be used to understand the most basic questions of human thought as well as specific questions regarding the society that produced them. Based on this idea, the myths of different peoples are perceived as informative with respect to their Ethnomathematics. Thus, together with work activities, myths constitute a source of support on which we draw to develop this line of research.