Modifications are proposed to the Stillinger-Weber potential, a semiempirical interaction potential for silicon. The modifications are specifically intended to improve the description of the amorphous phase. The potential is adjusted to reproduce the location of the transverse optic (TO) and transverse acoustic (TA) peaks of the vibrational density of states. These modifications also lead to ex...

Empirical methods have been successful in recent years. Indeed, as Henry Kautz reminded the workshop participants, in the last year alone, the New York Times has reported two major empirical successes: (1) DEEP BLUE’s defeat of Kasparov and (2) the computer-generated proof of an open problem in Robbins algebra. Pandurang Nayak (NASA Ames) described another highly publicized success, the diagnos...

Parametric empirical Bayes PEB may perform poorly when the assumed prior distribution is seriously invalid Nonparametric empirical Bayes NEB is more robust since it imposes no restric tion on the prior But compared with the PEB the NEB may be ine cient for small to medium samples due to the large variation and under dispersion of the NPMLE of the prior Using Monte Carlo simulations we compare t...

A semi-Markov process stays in state x for a time s and then jumps to state y according to a transition distribution Q(x; dy; ds). A statistical model is described by a family of such transition distributions. We give conditions for a nonparametric version of local asymptotic normality as the observation time tends to innnity. Then we introducèempirical' estimators for linear functionals of the...