Medicare’s Prospective Payment System (PPS) reform in 1983 tied hospital payments to the national average cost of each medical technology with the expectation of reducing health care costs. I show that an unintended consequence of PPS was generating financial incentives for hospitals to expand treatments that had average costs greater than marginal costs due to sizable fixed investments – i.e.,...

We consider the exclusive decay B → J/ψK using the QCD-improved factorization method in the heavy quark limit. It is shown that the decay amplitude is factorizable in this limit and nonfactorizable contributions are calculable from first principles in perturbation theory. Also the spectator contributions at order αs are finite and suppressed in the heavy quark limit. We present the result at ne...

We develop a theory of how community-level ethnic heterogeneity determines the formation of sexual networks, and how this, in turn, a¤ects the spread of HIV/AIDS. Speci…cally, the model assumes that agents derive utility from sexual relationships, but sexual in…delity is prohibited and punished if detected by the cheated partner. We show that when information circulates more easily within ethni...

Recent experimental results on the static or quasistatic response of granular materials have been interpreted to suggest the inapplicability of the traditional engineering approaches, which are based on elasto-plastic models (which are elliptic in nature). Propagating (hyperbolic) or diffusive (parabolic) models have been proposed to replace the ‘old’ models. Since several recent experiments we...

Supporters of touch-screen voting claim it is a highly reliable voting technology, while a growing number of critics argue that paperless electronic voting systems are vulnerable to fraud. In this paper we use county-level data on voting technologies in the 2000 and 2004 presidential elections to test whether voting technology affects electoral outcomes. We first show that there is a positive c...

In this talk, we review the QCD calculations of the lepton spectrum from inclusive semileptonic B decay. We compare this prediction to that of the ACCMMmodel. This latter work was done in collaboration with Csaba Csaki. Invited Talk, Presented at WHEPP-3 Workshop in Madras This work is supported in part by funds provided by the U.S. Department of Energy (DOE) under contract #DE-AC02-76ER03069 a...

This study examines how much, if any, of the differences in retail gasoline prices between markets is attributable to differences in the composition of vertical contract types at gasoline stations in each market. The purchase of the independent retail gasoline chain, Thrifty, by ARCO provides a unique opportunity to examine the effects of changes in different vertical contract types on local re...

This study examines how much, if any, of the differences in retail gasoline prices between markets is attributable to differences in the composition of vertical contract types at gasoline stations in each market. The purchase of the independent retail gasoline chain, Thrifty, by ARCO provides a unique opportunity to examine the effects of changes in different vertical contract types on local re...