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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

THREE ESSAYS ON THE BLACK WHITE WAGE GAP

Ogunro, Nola 01 January 2009 (has links)
During the 1960s and early 1970s, the black – white wage gap narrowed significantly, but has remained constant since the late 1980s. The black – white wage gap in the recent period may reflect differences in human capital. A key component of human capital is labor market experience. The first chapter of this dissertation examines how differences in the returns and patterns of experience accumulation affect the black – white wage gap. Accounting for differences in the nature of experience accumulation does not explain the very large gap in wages between blacks and whites. Instead, the wage gap seems to be driven by constant differences between blacks and whites which may represent unobserved differences in skill or the effects of discrimination. The second chapter of the dissertation examines the role of discrimination in explaining the wage gap by asking whether statistical discrimination by employers causes the wages of never incarcerated blacks to suffer when the incarceration rate of blacks in an area increases. I find little evidence that black incarceration rates negatively affect the wages of never incarcerated blacks. Instead, macroeconomic effects in areas with higher incarceration rates play a more important role in explaining the variation in black wages. The third and final chapter of the dissertation examines the black – white wage gap and its determinants across the entire wage distribution to determine if the factors that are driving the wage gap vary across the distribution. I find that at the top of the conditional distribution, differences in the distribution of characteristics explain relatively more of the black – white wage gap than differences in the prices of characteristics. At the bottom of the conditional distribution, differences in the distribution of characteristics explain relatively more of the wage gap—although this finding varies across different specifications of the model.
2

Essays on Urban and Labor Economics

Hizmo, Aurel January 2011 (has links)
<p>In the first chapter of this dissertation I develop a flexible and estimable equilibrium model that jointly considers location decisions of heterogeneous agents across space, and their optimal portfolio decisions. Merging continuous-time asset pricing with urban economics models, I find a unique sorting equilibrium and derive equilibrium house and asset prices in closed-form. Risk premia for homes depend on both aggregate and local idiosyncratic risks, and equilibrium returns for stocks depend on their correlation with city specific income and house price risk. In equilibrium, very risk-averse households do not locate in risky cities although they may have a high productivity match with those cities. I estimate a version of this model using house price and wage data at the metropolitan area level and provide estimates for risk premia for different cities. The estimated risk premia imply that homes are on average about 20000 cheaper than they would be if owners were risk-neutral. This estimate is over 100000 for volatile coastal cities. I simulate the model to study the effects of financial innovation on equilibrium outcomes. For reasonable parameters, creating assets that correlate with city-specific risks increase house prices by about 20% and productivity by about 10%. The average willingness to pay for completing markets per homeowner is between $10000 and $20000. Productivity is increased due to a unique channel: lowering the amount of non-insurable risk decreases the households' incentive to sort on these risks, which leads to a more efficient allocation of human capital in the economy.</p><p>The second chapter of this dissertation studies ability signaling in a model of employer learning and statistical discrimination. In traditional signaling models, education provides a way for individuals to sort themselves by ability. Employers in turn use education to statistically discriminate, paying wages that reflect the average productivity of workers with the same given level of education. In this chapter, we provide evidence that graduating from college plays a much more direct role in revealing ability to the labor market. Using the NLSY79, our results suggest that ability is observed nearly perfectly for college graduates. In contrast, returns to AFQT for high school graduates are initially very close to zero and rise steeply with experience. As a result, from very beginning of the career, college graduates are paid in accordance with their own ability, while the wages of high school graduates are initially unrelated to their own ability. This view of ability revelation in the labor market has considerable power in explaining racial differences in wages, education, and the returns to ability. In particular, we find a 6-10 percent wage penalty for blacks (conditional on ability) in the high school market but a small positive black wage premium in the college labor market. These results are consistent with the notion that employers use race to statistically discriminate in the high school market but have no need to do so in the college market.</p> / Dissertation
3

Three Essays on Employer Learning and Statistical Discrimination

Zhu, Beibei 06 June 2013 (has links)
This dissertation consists of three essays studying employer learning and statistical discrimination of young workers in the U.S. labor market. The first chapter outlines the dissertation by discussing the motivations, methods, and research findings.<br /><br />Chapter two develops a framework that nests both symmetric and asymmetric employer learning, and derives testable hypotheses on racial statistical discrimination under different processes of employer learning. Testing the model with data from the NLSY79, we find that employers statistically discriminate against black workers on the basis of both education and race in the high school market where learning appears to be mostly asymmetric. In the college market, employers directly observe most parts of the productivity of potential employees and learn very little over time.<br /><br />In chapter three, we investigate how the process of employer learning and statistical discrimination varies over time and across employers. The comparison between the NLSY79 and the NLSY97 cohorts reveals that employer learning and statistical discrimination has became stronger over the past decades. Using the NLSY97 data, we identify three employer- specific characteristics that influencing employer learning and statistical discrimination, the supervisor-worker race match, supervisor\'s age, and firm size. Black high school graduates face weaker employer learning and statistical discrimination if they choose to work for a black supervisor, work for an old supervisor, or work in a firm of small size.<br /><br />In the last chapter, we are interested in the associations between verbal and quantitative skills and individual earnings as well as the employer learning process of these two specific types of skills. There exist significant differences in both the labor market rewards and employer learning process of verbal and quantitative skills between high school and college graduates. Verbal skills are more important than quantitative skills for high school graduates, whereas college-educated workers benefit greatly from having high quantitative skills but little from having high verbal skills. In addition, employers directly learn verbal skills and continuously learn quantitative skills in the high school market, but almost perfectly observe quantitative skills in the college market. / Ph. D.
4

Die dualistiese arbeidsmarkteorie

Uys, Marthina Dorathea 11 1900 (has links)
Text in Afrikaans / Summaries in English and Afrikaans / The orthodox school's explanation for wage differentials, unemployment and labour market discrimination and the policy measures which they proposed did not offer workable solutions to the problems of the day. During the late 1960s and early 1970s a group of American labour economists conducted field studies in American urban ghettos which resulted in the formulation of the dual labour market theory. In contrast with the orthodox approach, which emphasises free market forces and investment in human capital, the dual labour market theory focuses on the dual structure of the labour market. The labour market is divided between a primary (high-wage) and a secondary (low-wage) sector, with little or no mobility between the sectors. An oversupply of labour in the secondary sector and unemployment are the results. These labour market phenomena and dualism also characterise the South African labour market and should be taken into account when policy measures are formulated. / Loonverskille, werkloosheid en arbeidsmarkdiskriminasie is algemene verskynsels in arbeids· markte wereldwyd. Die ortodokse denkskool se verklaring vir die verskynsels en die beleidsmaatreels wat bulle voorste~ het met verloop van tyd ontevredenheid ontketen omdat dit geen werkbare oplossing vir die probleme van die dag kon hied nie. Gedurende die laat ·1960s en vroee 1970s het 'n groep Arnerikaanse arbeidsekonome verskeie veldstudies in verskillende Arneri· kaanse stedelike ghetto's geloods op soek na 'n meer aanvaarbare verklaring vir hierdie verskyn· sels. Uit hierdie veldstudies is die dualistiese arbeidsmarkteorie geformuleer. In teenstelling met die ortodokse benadering, wat Idem le op die werking van vrye markkragte en investering in menslike kapitaal, benadruk die dualistiese arbeidsmarkteorie die tweeledige struktuur van die arbeidsmark. Die arbeidsmark is verdeel tusssen 'n primere (hoogbesoldigde) en sekondere (laagbesoldigde) sektor, met min of geen mobiliteit tussen die sektore nie. Werkers se toegang tot die primere sektor word beperk, met 'n ooraanbod van arbeid in die sekondere sektor en werkloosheid as die gevolg. Hierdie arbeidsmarkverskynsels en dualisme is ook kenmerkend van die Suid·Afrikaanse arbeidsmark en beleidsmaatreels moet daarmee rekening hou / Economics and Management Sciences / M. Comm. (Economy)
5

Statistisk eller preferensbaserad diskriminering? : En studie om diskriminering baserad på kön och etnicitet i förhållande till socialt kapital / Statistical or Taste-based Discrimination? : A Study of Ethnic and Sex Discrimination in the Context of Social Capital

Birkeland, Fredrik, Rosander, Oscar January 2015 (has links)
Diskriminering leder till en samhällsekonomisk ineffektivitet och tar sig uttryck både på individ- och samhällsnivå. Tidigare forskning har kartlagt och påvisat förekomst av etnisk diskriminering och könsdiskriminering på flera marknader i Sverige, men det har inte kunnat klargöras om diskrimineringen är statistisk eller preferensbaserad. Med kunskap om diskrimineringens karaktär kan beslutsfattare skapa effektivare policyinstrument för att motverka den diskriminering som visats förekomma i det svenska samhället. Ett problem på forskningsområdet är att det saknas empiriska metoder för att kunna särskilja diskrimineringen mellan olika förklaringsmodeller. Syftet med studien är att genomföra ett vinjettexperiment för att kunna särskilja den statistiska och preferensbaserade diskrimineringsteorin för diskrimineringsgrunderna kön och etnicitet. Studien syftar till att undersöka diskrimineringen i en svensk kontext i sammanhang som involverar tillit och generositet. Med hjälp av ett vinjettexperiment samlas primärdata in från en webbenkät. Vinjettexperimentet syftar till att utsätta respondenten för två hypotetiska scenarier som fokuserar på socialt kapital; ett som mäter generositet och ett som mäter tillit. Scenarierna konstrueras så att respondenten möter en okänd person vars etnicitet och kön varierar på ett randomiserat sätt. Genom att studera skillnader i respondenternas svar kan eventuell diskriminering påvisas och diskrimineringens karaktär kan undersökas. Studien visar att det förekommer både etnisk diskriminering och könsdiskriminering när det gäller respondenternas tilltro och generositet mot främmande personer. Våra resultat visar att den etniska diskrimineringen är mer omfattande än könsdiskrimineringen. Resultatet ger ett samtidigt stöd för den statistiska och preferensbaserade diskrimineringsteorin, vilket indikerar att policyinstrument bör konstrueras för att bemöta både den ofullständiga information som den statistiska diskrimineringen grundar sig på samt den animositet som den preferensbaserade diskrimineringen grundar sig på.
6

Price responses to changes in costs and demand

Eriksson, Rickard January 2001 (has links)
A large theoretical and empirical literature has studied the response in prices to changes in demands and costs. Three of the essays in this thesis are empirical studies of price-setting. The most important reason for studying the properties of price adjustments is the possible link between pricing and the business cycle. One family of models deals with price rigidities. If prices adjust slowly to changes in costs or demand, it will magnify fluctuations in output. A second family of models examines price changes due to changes in intensity of competition. Many of these models build on the idea that changes in demand affect the possibility of maintaining implicit collusion. Cyclical changes in the intensity of competition may cause a cyclical pricing pattern that magnifies fluctuations in output. Another line of research models the effects of liquidity constraints on the business cycle. One possible effect is that prices in markets where consumers have switching costs may increase, if the firms are hit by increased liquidity constraints. As increased liquidity constraints are common in recessions, prices will get a counter-cyclical tendency, which magnifies fluctuations in output. Another reason for studying price-setting patterns is that they can give an indication of the form of interaction between competing firms, which are of importance for competition policy. The fourth essay models sex discrimination formally. It shows that it is possible that sex discrimination in the labor market might be due to self-fulfilling sex stereotypes on the distribution of time out for child care between men and women. Both an even and an uneven distribution of time out for child care are possible equilibria in the model. The four essays can be read separatelyEssay 1 Price Responses to Seasonal Demand Changes in the Swedish Gasoline MarketA common idea in a number of papers on cyclical pricing is that implicit price collusion may be affected by changes in demand. In these models, tacit collusion is modeled as a game where agents balance gains from deviating from the collusive price, thereby gaining a short-run profit, against the gains from maintaining collusion in future periods. If demand fluctuates, the gains from deviating is high in periods of high demand; collusion may still be sustainable, however, if the collusive price is allowed to vary with demand. A lower price in high demand states reduces the gains from deviating, since it reduces the gain from each unit sold in these demand states. Hence, in order to equalize the profit from deviating and the profit from sticking to the implicit agreement, the price must move in the opposite direction to demand. Changes in demand can, naturally, be correlated with other factors affecting the price, such as cost changes. Thus, prices do not necessarily fall when demand increases in the data. According to the theory the, however, increase in demand should add a tendency to lower prices in order to make implicit collusion sustainable. The basic idea that changes in demand should affect prices if firms are engaged in implicit collusion has been employed in a number of papers, with different models for different assumptions on the pattern of demand changes. The demand for gasoline in Sweden follows a seasonal cycle, with demand being 42 percent higher in July than in January. Haltiwanger and Harrington provide a theory for implicit collusion over deterministic cycles, such as the seasonal cycle. Borenstein and Shepard (1996) tested Haltiwanger and Harrington’s model on the American gasoline retail market and found support for the theory. In this essay the model is tested for Swedish data, but no support for this theory is found. It is also investigated whether the effects on margins of the demand fluctuations induced by tax increases are compatible with theories of implicit collusion, but this is found not to be the case.Essay 2 Price Adjustments by a Gasoline Retail ChainEssay 2 is joint with Marcus Asplund and Richard Friberg. Stickiness of prices is an important building block in many business cycle models. This has spurred an empirical literature on price adjustments. Different types of price rigidities have different policy implications. Price setting can be state dependent, e.g. prices are adjusted when costs have changed by at least some minimal amount since the last price adjustment, or time-dependent e.g. adjusted once a week or once a year. Another issue is whether prices are equally rigid downwards as upwards. The second essay examines price responses in the Swedish gasoline retail market to changes in the Rotterdam spot price of gasoline, exchange rates and taxes. The main results are that cost changes are not fully passed through in the short run, but gradually moves towards the long-run equilibrium. Prices are stickier downwards than upwards. There is a minimum absolute size of price changes. Only very limited evidence of time-dependent price setting is found.Essay 3 Prices, Margins and Liquidity Constraints: Swedish Newspapers 1990-1996Essay 3 is written with Marcus Asplund and Niklas Strand. Chevalier and Scharfstein (1996) provide a model where consumer switching costs in combination with liquidity constraints give rise to a counter-cyclical tendency in prices. Customer stocks can be viewed as an investment, when consumers have switching costs when changing suppliers. Firms can exploit captured customers by setting a high price to raise short-run profits. However, a high price will induce consumers to search for alternatives, and customers once lost are costly to win back. Liquidity constraints, for instance in recessions, may force firms to sacrifice long-run profits for short-run gains. In this case, firms may have to cut back on investments in customer stocks by raising prices. Using firm level data from the Swedish daily newspaper industry, we test the effects of liquidity constraints on prices in markets with consumer switching costs. The newspaper industry is of particular interest, since firms set prices in two markets, the subscription market, where switching costs are high, and the advertising market, where switching costs are low. With accounting data from newspaper firms we can, by solvency, broadly categorize them as being more or less liquidity constrained. When Sweden enters a recession at the beginning of the nineties, we find a relative increase in subscription prices and margins for liquidity constrained firms. This is not the case for advertising prices, however. The results support the theory.Essay 4 Statistical Discrimination and Sex Stereotypes in the Labor MarketTime out for child care is unevenly distributed between the sexes. Parental leave benefits are usually exclusively given to the mother or distributed to both parents according to their choice. In Sweden, one month is reserved for each parent, however. One reason for this is to give the child better contact with both parents, but increased equality between the sexes in the labor market has also been put forward as an argument. This argument implicitly rests on the idea that sex stereotypes create sex discrimination, and that sex discrimination affects the distribution of time out for child care between the sexes. Essay 4 investigates if the uneven distribution of time out for child care can be explained by self-fulfilling sex stereotypes. It provides a model of distribution of time out for child care based on statistical discrimination and human capital investments. The model has three equilibria. In one equilibrium, time out for child care is evenly distributed between the sexes. In the second equilibrium, there is full specialization. The third equilibrium is an intermediate case, where time out for child care is unevenly distributed without full specialization There are no differences in ability or variance of ability between the sexes, the only differences between the equilibria are the self-fulfilling expectations of firms and workers. / Diss. (sammanfattning) Stockholm : Handelshögsk., 2001
7

Die dualistiese arbeidsmarkteorie

Uys, Marthina Dorathea 11 1900 (has links)
Text in Afrikaans / Summaries in English and Afrikaans / The orthodox school's explanation for wage differentials, unemployment and labour market discrimination and the policy measures which they proposed did not offer workable solutions to the problems of the day. During the late 1960s and early 1970s a group of American labour economists conducted field studies in American urban ghettos which resulted in the formulation of the dual labour market theory. In contrast with the orthodox approach, which emphasises free market forces and investment in human capital, the dual labour market theory focuses on the dual structure of the labour market. The labour market is divided between a primary (high-wage) and a secondary (low-wage) sector, with little or no mobility between the sectors. An oversupply of labour in the secondary sector and unemployment are the results. These labour market phenomena and dualism also characterise the South African labour market and should be taken into account when policy measures are formulated. / Loonverskille, werkloosheid en arbeidsmarkdiskriminasie is algemene verskynsels in arbeids· markte wereldwyd. Die ortodokse denkskool se verklaring vir die verskynsels en die beleidsmaatreels wat bulle voorste~ het met verloop van tyd ontevredenheid ontketen omdat dit geen werkbare oplossing vir die probleme van die dag kon hied nie. Gedurende die laat ·1960s en vroee 1970s het 'n groep Arnerikaanse arbeidsekonome verskeie veldstudies in verskillende Arneri· kaanse stedelike ghetto's geloods op soek na 'n meer aanvaarbare verklaring vir hierdie verskyn· sels. Uit hierdie veldstudies is die dualistiese arbeidsmarkteorie geformuleer. In teenstelling met die ortodokse benadering, wat Idem le op die werking van vrye markkragte en investering in menslike kapitaal, benadruk die dualistiese arbeidsmarkteorie die tweeledige struktuur van die arbeidsmark. Die arbeidsmark is verdeel tusssen 'n primere (hoogbesoldigde) en sekondere (laagbesoldigde) sektor, met min of geen mobiliteit tussen die sektore nie. Werkers se toegang tot die primere sektor word beperk, met 'n ooraanbod van arbeid in die sekondere sektor en werkloosheid as die gevolg. Hierdie arbeidsmarkverskynsels en dualisme is ook kenmerkend van die Suid·Afrikaanse arbeidsmark en beleidsmaatreels moet daarmee rekening hou / Economics and Management Sciences / M. Comm. (Economy)
8

Software for Manipulating and Embedding Data Interrogation Algorithms Into Integrated Systems

Allen, David W. 20 January 2005 (has links)
In this study a software package for easily creating and embedding structural health monitoring (SHM) data interrogation processes in remote hardware is presented. The software described herein is comprised of two pieces. The first is a client to allow graphical construction of data interrogation processes. The second is node software for remote execution of processes on remote sensing and monitoring hardware. The client software is created around a catalog of data interrogation algorithms compiled over several years of research at Los Alamos National Laboratory known as DIAMOND II. This study also includes encapsulating the DIAMOND II algorithms into independent interchangeable functions and expanding the catalog with work in feature extraction and statistical discrimination. The client software also includes methods for interfacing with the node software over an Internet connection. Once connected, the client software can upload a developed process to the integrated sensing and processing node. The node software has the ability to run the processes and return results. This software creates a distributed SHM network without individual nodes relying on each other or a centralized server to monitor a structure. For the demonstration summarized in this study, the client software is used to create data collection, feature extraction, and statistical modeling processes. Data are collected from monitoring hardware connected to the client by a local area network. A structural health monitoring process is created on the client and uploaded to the node software residing on the monitoring hardware. The node software runs the process and monitors a test structure for induced damage, returning the current structural-state indicator in near real time to the client. Current integrated health monitoring systems rely on processes statically loaded onto the monitoring node before the node is deployed in the field. The primary new contribution of this study is a software paradigm that allows processes to be created remotely and uploaded to the node in a dynamic fashion over the life of the monitoring node without taking the node out of service. / Master of Science
9

Essays on Labor Economics and International Trade

Danyang Zhang (12437343) 20 April 2022 (has links)
<p>  </p> <p>My dissertation is composed of three independent chapters in the field of labor economics and international trade. </p> <p><br></p> <p>The first chapter studies marriage market signaling and women’s occupation choice. Despite the general closure of gender disparities in the labor market over the past half century, occupational segregation has been stubbornly persistent. I develop a new model that explains these occupational outcomes through marriage market signaling. Vertically differentiated men have preference over women’s unobservable caregiving ability. Heterogenous women choose caregiving occupations to signal their ability to be caregivers. My model generates unique predictions on the influence of marriage market conditions on women’s occupational choices. I find empirical support for these predictions using longitudinal data on marriage rates, policy shocks to divorce laws, and shocks to the marriage market sex ratio driven by waves of immigration. </p> <p><br></p> <p>The second chapter investigates Covid19 and consumer animus towards Chinese products. Covid19 has tremendously affected all areas of our lives and our online shopping behaviors have not been immune. China is the first country to report cases of Covid19 and suffers from rising animus in the U.S. In this paper, we study consumer animus towards Chinese products post Covid19 using Amazon data. We tracked all face masks sold on Amazon between Sep. 2019 to Sep. 2020, and collect product information that is available to a real consumer, including reviews. By analyzing both seller-generated (e.g., product name, description, features) and user-generated (e.g., reviews and customer Q&A) content, we collect information on the country-of-origin as well as consumer animus for the products. Under a fully-dynamic event study design, we find that the average rating drops significantly after a product is identified as made in China for the first time, while no such drop is found for products with other countries-of-origin. This negative impact is U-shaped, which quickly expands in the first five weeks, and then gradually fades out within six months. An informative-animus review affects the average rating of a Chinese product both directly (through its own rating) and indirectly (through other future ratings), with both mechanisms supported in data. We also provide strong evidence that the drop in average rating is driven by consumer animus instead of product quality. </p> <p><br></p> <p>The third chapter explores how cultural transmission through international trade affects gender discrimination. In this paper, I propose that international trade helps alleviate gender discrimination. With imperfect information on workers’ ability, there is statistical discrimination towards female workers. Through international trade, culture transmits asymmetrically between firms located in countries with different gender cultures. This cultural transmission benefits women because it transmits only in one direction from more gender-equal cultures to less gender-equal cultures. I prove this by linking the Customs data to the Industrial Firms data of China in 2004, and find that Chinese firms trading with more gender-equal cultures hire a higher fraction of female workers and enjoy higher profits. Similar patterns are not found in Chinese firms trading with less gender-equal cultures. The impact of cultural transmission goes beyond the firms engaged in international trade to have spillover effects onto purely domestic firms. Comparing across skill groups, cultural transmission benefits high-skill female workers more.</p>
10

Essays on the formation of social networks from a game theoritical approach

Rubí Barceló, Antoni 08 February 2008 (has links)
This thesis aims to contribute to a fundamental objective of Network Economics: to provide based incentives explanations of real social network topologies. By using game theoretical tools, the three papers of this thesis analyze how real social networks can arise from the strategic interaction of self-interested individuals.In the first paper, we discuss the influence of imperfect information on the process of social network formation and, specifically, on the possibilities of observing racially segregated societies when agents' preferences are not racially biased. The second work attempts to complete the Network Economics' explanation of the puzzle regarding how agents can benefit from structural holes over a long time period. The third paper presents a model that focuses on the mechanisms underlying the formation of scientific collaboration networks. We show how researchers' heterogeneity and limited processing capability explain the basic characteristics of these networks. / Aquesta tesi aspira a contribuir a un objectiu fonamental de l'Economia de Xarxes: oferir explicacions basades en els incentius de les topologies que adopten les xarxes socials. Usant les eines de la Teoria de Jocs, els tres articles de la tesi analitzen com les xarxes socials que observem a la realitat poden esser fruit de la interacció entre individus que responen als seus propis interessos.En primer lloc, estudiem la influència de la informació imperfecte en la formació de xarxes socials i, específicament, en les possibilitats de tenir societats racialment segregades quan les preferències dels agents no estan racialment esbiaixades. El segon treball, intenta completar l'explicació que l'Economia de Xarxes dóna a l'interrogant referent als forats estructurals i a la gent que s'en beneficia de manera continuada. El darrer capítol, se centra en els mecanismes que expliquen la formació de xarxes de col·laboració científica. Es mostra com l'heterogeneïtat i la limitada capacitat de processament dels investigadors expliquen les caractarístiques bàsiques d'aquestes xarxes.

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