The decades-long effort to produce a workable HIV vaccine has hardly been a waste of public and private resources. To the contrary, the scientific know-how acquired along the way has served as the critical foundation for the development of vaccines against the novel, pandemic SARS-CoV-2 virus....

A significant competition for order flow in options markets occurred in August 1999. Before the competition, the majority of option volume arose from exclusive listings. By the end of September 1999, entry by existing option exchanges had shifted the majority of option volume to multiple-listing...

Objective: We evaluated the impact of Seguro Popular (SP), a program introduced in 2001 in Mexico primarily to finance health care for the poor. We studied the effect of SP on pregnant women's access to obstetrical services. Data: We analyzed the cross-sectional 2006 National Health and...

On January 20, 1997, the Securities and Exchange Commission began requiring Nasdaq market makers to execute or display customer limit orders. In addition, Nasdaq began displaying quotes placed by market makers to execute or display customer limit orders. In addition, Nasdaq began displaying...

We critically analyze the currently available status indicators of the COVID-19 epidemic so that state governors will have the guideposts necessary to decide whether to further loosen or instead retighten controls on social and economic activity. Overreliance on aggregate, state-level data in...

New York City has been rightly characterized as the epicenter of the coronavirus pandemic in the United States. Just one month after the first cases of coronavirus infection were reported in the city, the burden of infected individuals with serious complications of COVID-19 has already...

New York City's multipronged subway system was a major disseminator - if not the principal transmission vehicle - of coronavirus infection during the initial takeoff of the massive epidemic that became evident throughout the city during March 2020. The near shutoff of subway ridership in...