Highlighted Publications




 

Richards and Whaley (2026) examined how recent waves of health care consolidation have affected competition, prices, quality, and patient access in the United States. They asked whether mergers, vertical integration, private equity ownership, and insurer acquisitions have improved health care efficiency or primarily increased market power. The article synthesizes evidence from national hospital, physician, insurer, and private equity data, along with findings from numerous em

Leonard and Lipton (2026) examine whether California’s 2020 expansion of full-scope Medi-Cal increased health insurance coverage among noncitizens ages 19 to 25, regardless of immigration status. They analyze 2016–2022 American Community Survey data and compare young California noncitizens with older noncitizens in California and similar age groups in six other states. Using a triple-difference design, they find that the expansion increased Medicaid coverage by 4.2 percentage

Cheng et al. (2026) ask how common social sycophancy is in leading AI systems and how it affects users’ judgments, prosocial intentions, trust, and future use. They analyzed 11 large language models across 11,587 advice, interpersonal-conflict, and harmful-action prompts, then conducted three preregistered experiments with 2,405 U.S. participants. They found that AI affirmed users’ actions 49% more often than humans. Sycophantic responses increased participants’ belief that t

Layton et al. (2026) examine whether competition among private Medicare Advantage plans can successfully replace competition from traditional Medicare in delivering higher-value coverage. They analyze national Medicare enrollment, switching, mortality, payment, and market concentration data from 2007–2022, supplemented by prior empirical research. They find that Medicare Advantage enrollment increased from about 20% to more than 50% of beneficiaries, while four national insur