The Effect of Medicaid Expansion on Utilization in Maryland Emergency Departments.

Study Objective: A proposed benefit of expanding Medicaid eligibility under the Patient Protection and Affordable Care Act (ACA) was a reduction in emergency department (ED) utilization for primary care needs. Pre-ACA studies found that new Medicaid enrollees increased their ED utilization rates, but the effect on system-level ED visits was less clear. Our objective was to estimate the effect of Medicaid expansion on aggregate and individual-based ED utilization patterns within Maryland.

Endogenous Group Formation via Unproductive Costs.

Sacrifice is widely believed to enhance cooperation in churches, communes, gangs, clans, military units, and many other groups. We find that sacrifice can also work in the lab, apart from special ideologies, identities, or interactions. Our subjects play a modified VCM game-one in which they can voluntarily join groups that provide rates of return on private investment.

The Determinants of Federal and State Enforcement of Workplace Safety Regulations: OSHA Inspections 1990-2010.

We explore the determinants of inspection outcomes across 1.6 million Occupational Safety and Health Agency (OSHA) audits from 1990 through 2010. We find that discretion in enforcement differs in state and federally conducted inspections.

An agent-based model of centralized institutions, social network technology, and revolution.

This paper sheds light on the general mechanisms underlying large-scale social and institutional change. We employ an agent-based model to test the impact of authority centralization and social network technology on preference falsification and institutional change. We find that preference falsification is increasing with centralization and decreasing with social network range.