The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), a means-tested in-kind transfer nutritional assistance program, distributes infant formula to its beneficiaries using private retail stores. The program, which accounts for 40% of the infant formula market, reduces costs by auctioning public market monopoly rights to a single brand. We document that WIC increases the market power of its favored brand in the public market, plausibly due to scale economy in retailers' inventory costs that are internal to each brand. Retailers have thus caused private market spillovers by restricting the availability of non-favored brands, effectively foreclosing competition. We recover over 10,000 U.S. grocery retailers' inventory costs of infant formula in a scanner dataset where inventory decisions are unobservable; we use these estimates, combined with a vertical model of the industry, to quantify the trade-off between the government's bargaining power over prices and consumer welfare in the private market.

Rigid and broad market definitions can misrepresent consumption patterns and misguide resource allocation and policy decisions. We develop a new framework that flexibly defines overlapping markets at the consumer level by modeling consumption flows across space. Applied to the U.S. Health Professional Shortage Area (HPSA) designations, our approach estimates 11.6 million people lack adequate access to primary care physicians (PCPs) — far fewer than the 30–100 million identified by HPSAs. Simulations indicate that allocating 3,734 additional PCPs could eliminate shortages nationwide. These findings underscore the importance of flexible market delineation and offer actionable guidance for improving primary care access.

Between 2010 and 2017, thousands of urgent care centers (UCCs) opened across the United States, raising questions about how their entry affects health care use and prescribing. Using Medicare claims data and newly compiled data about UCC openings, we compared changes in outpatient visits and prescription drug use in ZIP codes with UCC entry to contemporaneous changes in areas without. UCC entry led to small increases in outpatient visits and prescriptions overall. This included increases of 0.89 percent and 1.59 percent increases in prescriptions for antibiotics and psycholeptic medications, respectively. In areas with lower primary care availability, UCC entry led to significantly higher prescribing of antibiotics, opioids, and psycholeptics without an associated increase in visits. These findings suggest that UCCs may expand access to treatment in underserved areas but may also increase use of potentially high-risk medications.