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Showing papers by "David Martin published in 1995"


Proceedings ArticleDOI
06 Nov 1995
TL;DR: SRI International participated in the MUC-6 evaluation using the latest version of SRI's FASTUS system as mentioned in this paper, which is a cascaded finite state transducers, each providing an additional level of analysis of the input and merging of the final results.
Abstract: SRI International participated in the MUC-6 evaluation using the latest version of SRI's FASTUS system [1]. The FASTUS system was originally developed for participation in the MUC-4 evaluation [3] in 1992, and the performance of FASTUS in MUC-4 helped demonstrate the viability of finite state technologies in constrained natural-language understanding tasks. The system has undergone significant revision since MUC-4, and it is safe to say that the current system does not share a single line of code with the original. The fundamental ideas behind FASTUS, however, are retained in the current system: an architecture consisting of cascaded finite state transducers, each providing an additional level of analysis of the input, together with merging of the final results.

241 citations


01 Jan 1995
TL;DR: SRI International participated in the MUC-6 evaluation using the latest version of SRI's FASTUS system, an architecture consisting of cascaded finite state transducers, each providing an additional level of analysis of the input, together with merging of the final results.

144 citations


Proceedings ArticleDOI
01 Dec 1995
TL;DR: The UNOS Liver Allocation Model (ULAM) as mentioned in this paper is a simulation model that supports policy evaluation for a national medical problem, which is used for liver allocation in a complex political, economic and social environment.
Abstract: The paper on the UNOS Liver Allocation Model (ULAM) describes the building of a simulation model that supports policy evaluation for a national medical problem. The modeling and simulation techniques used in building ULAM include: fitting donor and patient arrival processes having trend and cyclic rate components using non-homogeneous Poisson processes (NHPPs) having exponential rate functions which may include both a polynomial and some trigonometric components, fitting distributions to data on transition times between states of medical urgency; application of variance reduction techniques using common random-number streams and prior information; organizing data structures for efficient file searching and ranking capabilities; the use of bootstrapping techniques for attribute sampling; the building of submodels employing biostatistical procedures such as Kaplan-Meier and logistic regression; and the characterization of performance measures within a complex political, economic and social environment. ULAM provides a means for producing quantitative information to support the selection of a liver allocation policy.

58 citations