A Machine Learning Approach to Improving Occupational Income Scores

Historical studies of labor markets frequently lack data on individual income. The occupational income score (OCCSCORE) is often used as an alternative measure of labor market outcomes. We consider the consequences of using OCCSCORE when researchers are interested in earnings regressions. We estimate race and gender earnings gaps in modern decennial Censuses as well as the 1915 Iowa State Census. Using OCCSCORE biases results towards zero and can result in estimated gaps of the wrong sign. We use a machine learning approach to construct a new adjusted score based on industry, occupation, and demographics. The new income score provides estimates closer to earnings regressions. Lastly, we consider the consequences for estimates of intergenerational mobility elasticities

Trade competition and migration: Evidence from the quartz crisis

Foreign competition and technological change can both present threats to domestic industries, potentially resulting in out-migration from cities and regions where these industries are spatially agglomerated. In this paper, I study the migration effects of one such trade shock: The quartz crisis, which devastated the globally dominant Swiss watch industry in the 1970s. Using a differences-in-differences strategy, I show that this trade shock led to a rapid loss of population in affected areas, and a long-run change in growth patterns. This contrasts with many other studies of large trade shocks, which find little migration response. I highlight three key factors that distinguish this shock from others and may explain the divergence: (1) the crisis negatively impacted a key export industry while generating no offsetting gains, (2) the affected labor markets were highly non-diversified, and (3) the affected workers were highly mobile

Why living in an area with more businesses and denser housing might help keep you safer on the street

Recent decades have seen two important trends in America's cities: a return of young professionals to previously neglected urban cores, and a dramatic decline in violent crime. In new research, which explores these patterns, Tate Twinam examines the link between crime and the density of land use in Chicago. He finds that in residential areas that also contain shops and other businesses, the denser the housing, the lower the rate of robberies and street assaults

The economics of zoning

This dissertation consists of three chapters. Chapter 1 examines the identification power of assumptions that formalize the notion of complementarity in the context of a nonparametric bounds analysis of treatment response. I extend the literature on partial identification via shape restrictions by exploiting cross--dimensional restrictions on treatment response when treatments are multidimensional; the assumption of supermodularity can strengthen bounds on average treatment effects in studies of policy complementarity. I combine this restriction with a statistical independence assumption to derive improved bounds on treatment effect distributions, aiding in the evaluation of complex randomized controlled trials. I show how complementarities arising from treatment effect heterogeneity among subpopulations can be incorporated through supermodular instrumental variables to strengthen identification of treatment effects in studies with one or multiple treatments. I use these results to examine the long--run effects of zoning on the evolution of land use patterns. Chapter 2 considers the determinants of land use regulation. Zoning has been cited as a discriminatory policy tool by critics, who argue that ordinances are used to deter the entry of minority residents into majority neighborhoods through density restrictions (exclusionary zoning) and locate manufacturing activity in minority neighborhoods (environmental racism). However, identifying discrimination in these regulations is complicated by the fact that land use and zoning have been co-evolving for nearly a century. We employ a novel approach to overcome this challenge, studying the introduction of comprehensive zoning in Chicago. We find evidence of a pre-cursor to exclusionary zoning as well as inequitable treatment in industrial use zoning. Chapter 3 examines the impact of residential density and mixed land use on crime using a unique high-resolution dataset from Chicago over the period 2008-2013. I employ a novel instrumental variable strategy based on the city's 1923 zoning code. I find that commercial uses lead to more street crime in their immediate vicinity, with relatively weak spillovers. However, this effect is strongly offset by density; dense mixed use areas are actually safer than typical residential areas. Additionally, much of the commercial effect is driven by liquor stores and late-hour bars. I discuss the implications for zoning policy

Informational Efficiency of Decision Markets with Risk-Averse Insiders and Uncertain Manipulation

(Statement of Responsibility) by Tate A. Twinam(Thesis) Thesis (B.A.) -- New College of Florida, 2010(Electronic Access) RESTRICTED TO NCF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE(Bibliography) Includes bibliographical references.(Source of Description) This bibliographic record is available under the Creative Commons CC0 public domain dedication. The New College of Florida, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.(Local) Faculty Sponsor: Elliot, Catherin