Knowledge that Transforms

The relations between unobserved events and observed outcomes can be characterized by a bipartite graph. We propose an algorithm that explores the structure of the graph to construct the “exact Core Determining Class,” i.e., the set of irredudant inequalities. We prove that in general the exact Core Determining Class does not depend on the probability measure of the outcomes but only on the structure of the graph. For more general linear inequalities selection problems, we propose a statistical procedure similar to the Dantzig Selector to select the truly informative constraints. We demonstrate performances of our procedures in Monte-Carlo experiments.

Structural estimation of matching games with transferable utility, including matching games of trading networks and many-to-many matching, is increasingly popular in empirical work. I explore several modeling decisions that need to be made when specifying a structural model for a matching game. One decision is the choice of a game theoretic solution concept to impose in the structural model. I discuss pairwise stability, competitive equilibrium, and noncooperative games such as auctions. Another decision is whether to work with a continuum of agents or a finite number of agents. I explore other issues as well.

Asymmetric information is a key feature of the marriage market. In HIV-endemic settings, HIV risk is an important partner attribute that may influence marriage timing and partner selection. We use a sample of married women in rural Malawi to validate a model of positive assortative matching under asymmetric information. Several correlations support this framework, suggesting that HIV risk contributes to adverse selection in the marriage market in this setting.

Manmade climate change (CC) has catastrophic consequences. The United States has already experienced wholesale population realignment due to climate as households have relocated to the Sunbelt and West. The irony is that people are moving toward the heat and major storms associated with CC. As CC intensifies, with high rates of internal US factor mobility, firms and households will likely again relocate to areas with higher utility and profits, reducing CC costs. Yet current research typically focuses on CC costs in a given location without considering this realignment. We propose several avenues to overcome such shortcomings in US CC modeling.

I propose a new solution concept, obvious ex post (OXP) equilibrium. This is a formal standard of cognitive simplicity for mechanisms, in settings with interdependent values. Under some standard assumptions, the ascending auction has an efficient OXP equilibrium. I discuss a decision theoretic foundation for OXP mechanisms.

This research paper builds on previous literature and documents general changes in the labor market for Native American women that occurred during the Great Recession using extracts of data from the Current Population Survey Annual Earnings file, known as the Merged Outgoing Rotation Groups (MORG). Wages, unemployment, and other labor market variables for Native American women are contrasted with those of Native American men and white women to determine the relative change in labor market inequality that occurred during the Great Recession.

How might policies that promote marriage and/or dissuade divorce help in the fight against HIV/AIDS? This question is addressed employing a choice-theoretic general equilibrium search model, using Malawi as a case study. In the framework developed, individuals can choose between married and single life. A single person can select among abstinence and sex with or without a condom. The results suggest that marriage-friendly policies can help to abate HIV/AIDS. The policy predictions that obtain from general equilibrium analysis are compared with those that arise from simulated synthetic field experiments and epidemiological studies.

Who fought the War on Terror? We find that as the wars in Iraq and Afghanistan progressed, there was an increase in the fraction of active-duty Army enlistees who were white or from high-income neighborhoods and that these two groups selected combat occupations more often. Among men, we find an increase in deployment and combat injuries for white and Hispanic soldiers relative to black soldiers and for soldiers from high-income neighborhoods relative to those from low-income neighborhoods. This finding suggests that an all-volunteer force does not compel a disproportionate number of non-white and low socio-economic men to fight America's wars.

We present a class of one-to-one matching models with perfectly transferable utility. We discuss identification and inference in these separable models, and we show how their comparative statics are readily analyzed.