I investigate how changes in fees paid to Medicaid physicians affect take-up among children in low-income families. The existing literature suggests that the low level of Medicaid fee payments to physicians reduces their willingness to see Medicaid patients, thus creating an access-to-care problem for these patients. For the identical service, current Medicaid reimbursement rates are only about 65 percent of those covered by Medicare. Increasing the relative payments of Medicaid would increase its perceived value, as it would provide better access to health care for Medicaid beneficiaries. Using variation in the timing of the changes in Medicaid payment across states, I find that increasing Medicaid generosity is associated with both an increase in take-up and a reduction in uninsured rate. These results provide a partial answer to the puzzling question of why many low-income children who are eligible for Medicaid remain uninsured. JEL classification: I11, I18

The Integrated Health Interview Series (IHIS) is a public data repository that harmonizes four decades of the National Health Interview Survey (NHIS). The NHIS is the premier source of information on the health of the U.S. population. Since 1957 the survey has collected information on health behaviors, health conditions, and health care access. The long running time series of the NHIS is a powerful tool for health research. However, efforts to fully utilize its time span are obstructed by difficult documentation, unstable variable and coding definitions, and non-ignorable sample re-designs. To overcome these hurdles the IHIS, a freely available and web-accessible resource, provides harmonized NHIS data from 1969-2010. This paper describes the challenges of working with the NHIS and how the IHIS reduces such burdens. To demonstrate one potential use of the IHIS we examine utilization patterns in the U.S. from 1972-2008.

Privacy is one of major concerns when data containing sensitive information needs to be released for ad hoc analysis, which has attracted wide research interest on privacy-preserving data publishing in the past few years. One approach of strategy to anonymize data is generalization. In a typical generalization approach, tuples in a table was first divided into many QI (quasi-identifier)-groups such that the size of each QI-group is no less than k. Clustering is to partition the tuples into many clusters such that the points within a cluster are more similar to each other than points in different clusters. The two methods share a common feature: distribute the tuples into many small groups. Motivated by this observation, we propose a clustering-based k-anonymity algorithm, which achieves k-anonymity through clustering. Extensive experiments on real data sets are also conducted, showing that the utility has been improved by our approach.

This paper studies a stable job matching equilibrium and the implicit pricing of non-wage job characteristics. It departs from the previous literature by allowing worker heterogeneity in productivity instead of preferences, giving rise to a double transaction problem in a hedonic model. We show explicitly how wage differences across jobs can be decomposed into compensating wage differentials for non-wage job characteristics and differences in worker productivity. We also derive sufficient conditions for an assortative job matching and a stable matching condition in a model with continuous agent types. Empirical evidence fromthe U.S. Census and job amenity data from the Dictionary of Occupational Titles strongly supports our theory.

For decades, policymakers in many American cities have called for measures to bolster road capacity and parking provision. Now there is growing concern at all levels of government that the resulting changes to the built environment and subsequent increases in automobile use negatively impact the livability and sustainability of cities. Unfortunately, these impacts are not well understood and there is limited knowledge regarding alternative approaches to the planning and design of transportation systems. ^ This research incorporates data from 14 small American cities over a period of 50 years to assess the considerable rises in automobile use, the increases in automobile infrastructure, and the associated impacts. The analysis in this study shows that an increase in automobile use of 10 percentage points is associated with an increase of more than 35 square feet of parking per person citywide and a decrease of 4,600 people per square mile. ^ This study also reveals that many cities have experienced increased automobile use for shorter trips within each city, which could easily be served by alternative modes. The evidence suggests this is likely due to improved automobile infrastructure (and a subsequent decay in the environment for walking and biking), intended to serve trips in and out of each city. These shorter automobile trips exacerbate the need for additional infrastructure and could be one potential area to better manage automobile use. ^ Lastly, this work provides an overview of policies that can be implemented which could help place greater emphasis on walking, biking, and transit. The research shows that in cities that have adopted these policies, transportation infrastructure takes up a smaller portion of land and there are considerably greater concentrations of residents and employees. These cases offer valuable lessons in how particular transportation policy can ultimately impact the vitality and the financial viability of cities.

This thesis contains three essays on real estate finance and economics. Both chapter 2 and chapter 3 study a real estate developer's timing strategies under uncertainty and chapter 4 studies the ratio of housing price-to-income. Chapter 2 analyzes the effects of leverage on the timing of developments because most real estate developers depend heavily on leverage. In particular, it investigates the leverage effects on real estate developments that involve conversion of land from agricultural to urban use. Leverage matters for a developer who wants to optimize the timing of developments. Chapter 3 studies the effects of heterogeneity of real assets on the timing of developments because each property is unique and its value is likely to move together with values of neighboring properties. Heterogeneity matters for a developer who builds multiple properties in a project. Chapter 4 analyzes the price-to-income ratio which has been used widely as a measure for housing bubble. A cross-city comparison of price-to-income ratios can overestimate bubble in cities of high amenities.

In this article, I examine the black-white crossover in U.S. adult all-cause mortality, emphasizing how cohort effects condition age-specific estimates of mortalityrisk. I employ hierarchical age-period-cohort methods on the National Health Interview Survey-Linked Mortality Files between 1986 and 2006 to show that the black-white mortality crossover can be uncrossed by factoring out period and cohort effects of mortality risk. That is, when controlling for variations in cohort and period patterns of U.S. adult mortality, the estimated age effects of non-Hispanic black and non-Hispanic white U.S. adult mortality risk do not cross at any age. This is the casefor both men and women. Further, results show that nearly all the recent temporal change in U.S. adult mortality risk was cohort driven. The findings support the contention that the non-Hispanic black and non-Hispanic white U.S. adult populations experienced disparate cohort patterns of mortality risk and that these different experiences are driving the convergence and crossover of mortality risk at older ages.

In the short-term, unemployment rates are unlikely to come down to their pre-recession levels without improvements in housing markets and consumer demand. Yet high educational attainment is essential for the health of metropolitan labor markets before, during, and after recessions. Educational attainment makes workers more employable, creates demand for complementary less educated workers, and facilitates entrepreneurship. To better train less educated adults, non-profit organizations, community colleges, and governments can use detailed job openings data to align training curricula and certifiable skills with employer demand.

Anti-discrimination laws on the basis of sexual orientation have been adopted by many states to counteract perceived discrimination in the labor market. We find that relative to married heterosexual men, homosexual men earn less and anti-discriminatory laws, over time, partially lessen this gap. This gap is statistically non-existent relative to un- married heterosexual men. Homosexual women, on the other hand, experience higher earnings than their heterosexual female counterparts, and the law shrinks this gap over time. Our results suggest that although the earnings differential may be due to the marriage premium, anti-discriminatory laws do help reduce labor market differences between homosexuals and heterosexuals. We conjecture that allowing homosexuals to marry could reduce the earnings inequality without creating potentially significant la- bor market distortions.

As the world becomes wealthier over time, inflation-adjusted insured damages from natural disasters go up as well. This article analyzes whether there is still a significant upward trend once insured natural disaster loss has been normalized. By scaling up loss from past disasters, normalization adjusts for the fact that a hazard event of equal strength will typically cause more damage nowadays than in past years because of wealth accumulation over time. A trend analysis of normalized insured damage from natural disasters is not only of interest to the insurance industry, but can potentially be useful for attempts at detecting whether there has been an increase in the frequency and/or intensity of natural hazards, whether caused by natural climate variability or anthropogenic climate change. We analyze trends at the global level over the period 1990 to 2008, over the period 1980 to 2008 for West Germany and 1973 to 2008 for the United States. We find no significant trends at the global level, but we detect statistically significant upward trends in normalized insured losses from all nongeophysical disasters as well as from certain specific disaster types in the United States and West Germany.

The early-life conditions of U.S. birth cohorts have markedly improved over the past 100 years. At the same time, education in adulthood has grown increasingly important in securing good health and lowering mortality risk. Consequently, at the population-level the long arm ofchildhood is growing shorter with respect to U.S. adult mortality risk. Further, these changes are associated with cohort forces that substantially differ for the U.S. white and black populations. We use the NHIS-LMF 1986-2006 and U.S. census data to illustrate how racial differences incohort patterns of U.S. adult mortality are tied to racial inequalities in both early-life conditions and disparate health returns to educational attainment. These long-term, cumulative, cohort processes sustain significant and substantive racial disparities in socioeconomic gradients of U.S. mortality.

What are the causal effects of collective bargaining (CB) on teacher salaries? This seemingly simple question is difficult to answer because (a) national data measuring school district salaries and collective bargaining is limited in scope, while individual teacher data from the CPS mismeasure CB coverage; (b) union wage effects depend not only on coverage but also on an array of CB law provisions difficult to quantify; (c) union coverage and state CB laws are endogenous since each has been influenced by union sentiment among workers and voters; and (d) OLS estimates of the wage effect of CB coverage and laws may be biased by measurement error and endogeneity. We attempt to address these issues using measures of historical labor sentiment, by creating indices of CB law strength, and by using alternative national data sets containing information on teacher salaries and coverage. As in prior studies, we find modest union salary effects for teachers using standard methods, albeit smaller than found for the private sector. A union benefits premium estimated from SASS substantially exceeds the salary premium. Estimates of CB law and coverage effects using IV (with historical data measuring labor sentiment as instruments) are unrealistically large. We then examine historical data on teacher salaries from 1949 through 2009. We find that in 1959 (the 1960 Census), prior to adoption of state CB laws and subsequent coverage, teacher salaries were higher in states that would eventually adopt CB laws and bargaining. By 1979 all but a few of the states that would pass CB laws had done so. The union salary advantage for teachers increased between 1959 and 1979. Our tentative assessment is that roughly half the 10 percent OLS salary advantage seen for union teachers is causally due to CB laws and coverage, while the other half is not caused by collective bargaining, resulting instead from pre-existing sentiment or other factors correlated with coverage.

This dissertation evaluates how the different contexts of reception in new and traditional immigrant settlement states shape the educational achievement of immigrants' children. The first essay examines how individual, family, school, and neighborhood academic resources differ between new and traditional settlement states and whether these differences contribute to diverging achievement patterns. The second essay examines how the relationship between settlement location and student achievement changed over time as more immigrants arrived and dispersed throughout the 1990s. This essay examines how socio-demographic, family, school, and neighborhood characteristics contributed to differing cohort achievement patterns for each settlement location. The third essay assesses how variation in immigration policies across these states contributes to the unequal academic achievement of immigrant youth. Specifically, the essay investigates whether traditional and new settlement states can reduce the dropout rate for their undocumented immigrant population by adopting in-state resident tuition policies that provide in-state tuition to undocumented students. In combination, this three essay dissertation provides policymakers and educators with critical information on how state-level policies and the characteristics of settlement communities influence the academic achievement of a growing and geographically dispersed immigrant population.

This paper utilizes a difference in difference framework to estimate the impact of September 11 on wages, hours worked, and probability of employment for individuals of Middle Eastern ancestry in the aftermath of the terrorist attacks. September 11th is associated with a 4-6% decrease in the wages of Middle Eastern individuals relative to whites, which corresponds to well-documented reports of a public opinion backlash. There is little evidence that September 11th had an impact of the probability of employment or hours worked per week of Middle Eastern individuals relative to whites. This paper contributes to the scarce existing literature by providing estimates of labor market discrimination for both women and men, and uses an innovative assignment technique on the basis of ancestry that allows for estimates including both immigrants and U.S. citizens.

In this paper, I consider the extent to which home ownership affects men's labor supply. Research on the labor-supply consequences of home ownership is complicated by the endogeneity of owner-occupied housing. To address this endogeneity problem, I use a set of family size instruments (the presence of the third and additional children) to estimate the effect of home ownership in a recursive bivariate probit model. Based on a sample of married white male household heads from the American Community Survey, the IV result suggests that men who own their homes are 1.2% more likely to be employed relative to those who rent. I also show that the relationship between home ownership and family size is highly nonlinear and non-monotonic. The first two children have positive influence on both home ownership and men's employment. The third and additional children are negatively associated with home ownership but have no significant incremental effects on men's labor supply.

A large body of recent research claims that racial diversity hinders the general trust of others, but these studies rarely consider how racial segregation mediates diversity. This article re-examines the issue by considering how the residential isolation of minorities alters general trust and one manifestation of trust: volunteering in cities. Using data from the US, the results from a regression analysis suggest that metropolitan-level racial segregation decreases trust and volunteering. Diversity has no significant effect. The results are robust to a variety of specifications and assumptions. The use of historical metropolitan and state characteristics improves the fit between segregation and distrust, and political affiliation is explored as a potential link between group distrust and general distrust. High levels of trust have been identified as a source of good governance and economic performance; integration is likely to enhance these attributes regardless of the level of diversity.