Department of Economics
http://hdl.handle.net/1721.1/7808
2014-10-02T10:51:20ZThe spatial clustering of occupations
http://hdl.handle.net/1721.1/90134
The spatial clustering of occupations
Swift, Henry Spencer
Workers in similar occupations cluster, much like firms in similar industries. This may be due to firm clustering, but I propose a supply-side mechanism that may also provide an explanation. When workers face a risk of separation from a particular job, they will consider the other jobs available in a particular area in their location decision. Based on this theory I make three predictions. Workers will tend to cluster in areas where their skills are in high demand. They will be paid less in these areas, ceteris paribus. And demand shocks will affect workers' wages less, and employment more, in areas where their skills are in high demand. I test this mechanism using data from the decennial U.S. Census. I use O*NET data on occupational tasks to construct a measure of occupational distance. I then estimate labor supply curves to determine to test the predictions of the theory. I do not find substantial evidence for this mechanism.
Thesis: S.M., Massachusetts Institute of Technology, Department of Economics, 2014.; "June 2014." Cataloged from PDF version of thesis.; Includes bibliographical references (pages 42-44).
2014-01-01T00:00:00ZOptimal taxation with endogenous wages
http://hdl.handle.net/1721.1/90133
Optimal taxation with endogenous wages
Stantcheva, Stefanie
This thesis consists of three chapters on optimal tax theory with endogenous wages. Chapter 1 studies optimal linear and nonlinear income taxation when firms do not know workers' abilities, and competitively screen them through nonlinear compensation contracts, unobservable to the government, in a Miyazaki-Wilson-Spence equilibrium. Adverse selection changes the optimal tax formulas because of the use of work hours as a screening tool, which for higher talent workers results in a "rat race," and for lower talent workers in informational rents and cross-subsidies. If the government has sufficiently strong redistributive goals, welfare is higher when there is adverse selection than when there is not. The model has practical implications for the interpretation, estimation, and use of taxable income elasticities, central to optimal tax design. Chapter 2 derives optimal income tax and human capital policies in a dynamic life cycle model with risky human capital formation through monetary expenses and training time. The government faces asymmetric information regarding the stochastic ability of agents and labor supply. When the wage elasticity with respect to ability is increasing in human capital, the optimal subsidy involves less than full deductibility of human capital expenses on the tax base, and falls with age. The optimal tax treatment of training time also depends on its interactions with contemporaneous and future labor supply. Income contingent loans, and a tax scheme with deferred deductibility of human capital expenses can implement the optimum. Numerical results suggest that full dynamic risk-adjusted deductibility of expenses is close to optimal, and that simple linear age-dependent policies can achieve most of the welfare gain from the second best. Chapter 3 considers dynamic optimal income, education, and bequest taxes in a Barro- Becker dynastic setup. Each generation is subject to idiosyncratic preference and productivity shocks. Parents can transfer resources to their children either through education investments, which improve the child's wage, or through financial bequests. I derive optimal linear tax formulas as functions of estimable sufficient statistics, robust to underlying heterogeneities in preferences. It is in general not optimal to make education expenses fully tax deductible. I also show how to derive equivalent formulas using reform-specific elasticities that can be targeted to already available estimates from existing reforms.
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Economics, 2014.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 199-207).
2014-01-01T00:00:00ZEssays in the industrial organization of the pharmaceutical industry
http://hdl.handle.net/1721.1/90132
Essays in the industrial organization of the pharmaceutical industry
Shapiro, Bradley T. (Bradley Thomas)
This dissertation comprises of three chapters, each exploring different issues in the industrial organization of the pharmaceutical industry. In the first chapter, I study the effects of television advertising of antidepressants using a novel method comparing households near the borders of television markets. I find that advertising has positive benefits on the market as a whole, including competitors. Using this information and a simple supply model, I consider the counterfactual whereby firms work together in a co-operative. In the co-operative equilibrium, firms advertise more than five times as much as is observed in competitive equilibrium and profits would increase by about twenty percent. In the second chapter, the documented phenomenon of strategic entry delay is analyzed in the sleep aid industry in order to measure the cost to consumers of that delay. With the Hatch-Waxman Act of 1984, the FDA included an unchallengeable exclusivity period for new approved drugs, independent of patents. This generates an incentive for firms to strategically delay the introduction of new versions of drugs until just before patent expiration of the originals in order to take market share away from new generics rather than its own original product in its time of FDA exclusivity. Using detailed prescribing and pricing data, I document that delay and estimate cost to consumers in the prescription sleep aid market at about $644 million over seven years. In the final chapter, we examine firm behavior following the loss of exclusivity (LOE) of six molecules between June 2009 and May 2013 that were among the 50 most prescribed molecules in May 2013. We analyze speed of generic firm entry, prices, generic and penetration separately by four payer types (cash, Medicare Part D, Medicaid, and other third party payer -TPP) and by age (under vs. over 65). We find modest price decreases following LOE but very rapid and complete penetration of generics. While on average molecule prices decrease, the branded versions continue to increase prices after LOE. Expansion of molecule sales is increasingly common. Generic penetration rates are typically highest and most rapid for TPPs, and lowest and slowest for Medicaid. Cash customers and seniors generally pay the highest prices, TPPs and those under 65 pay the lowest prices. The presence of an authorized generic is also analyzed and found to have effects that vary across molecule.
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Economics, 2014.; Cataloged from PDF version of thesis.; Includes bibliographical references.
2014-01-01T00:00:00ZExtrapolation and bandwidth choice in the regression discontinuity design
http://hdl.handle.net/1721.1/90131
Extrapolation and bandwidth choice in the regression discontinuity design
Rokkanen, Miikka
This thesis consists of three methodological contributions to the literature on the regression discontinuity (RD) design. The first two chapters develop approaches to the extrapolation of treatment effects away from the cutoff in RD and use them to study the achievement effects of attending selective public schools, known as exam schools, in Boston. The third chapter develops an adaptive bandwidth choice algorithm for local polynomial regression-based RD estimators. The first chapter develops a latent factor-based approach to RD extrapolation that is then used to estimate effects of exam school attendance for infra-marginal 7th grade applicants. Achievement gains from Boston exam schools are larger for applicants with lower English and Math abilities. I also use the model to predict the effects of introducing either minority or socioeconomic preferences in exam school admissions. Affirmative action has modest average effects on achievement, while increasing the achievement of the applicants who gain access to exam schools as a result. The second chapter, written jointly with Joshua Angrist, develops a covariate-based approach to RD extrapolation that is then used to estimate effects of exam school attendance for infra-marginal 9th grade applicants. The estimates suggest that the causal effects of exam school attendance for applicants with running variable values well away from admissions cutoffs differ little from those for applicants with values that put them on the margin of acceptance. The third chapter develops an adaptive bandwidth choice algorithm for local polynomial regression-based RD estimators. The algorithm allows for different choices for the order of polynomial and kernel function. In addition, the algorithm automatically takes into account the inclusion of additional covariates as well as alternative assumptions on the variance-covariance structure of the error terms. I show that the algorithm produces a consistent estimator of the asymptotically optimal bandwidth and that the resulting regression discontinuity estimator satisfies the asymptotic optimality criterion of Li (1987). Finally, I provide Monte Carlo evidence suggesting that the proposed algorithm also performs well in finite samples.
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Economics, 2014.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 150-160).
2014-01-01T00:00:00Z