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Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Social and Behavioral Sciences

1997

Selected Works

Articles 1 - 8 of 8

Full-Text Articles in Physical Sciences and Mathematics

Windows 3.X Vs. Windows 95: Get Your Ring-Side Seat, Sonya Shepherd Nov 1997

Windows 3.X Vs. Windows 95: Get Your Ring-Side Seat, Sonya Shepherd

Sonya S. Gaither

No abstract provided.

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The Role Of The Library In The Computerized Campus, Ryan Johnson, Sonya Shepherd, A. Mccrory Sep 1997

The Role Of The Library In The Computerized Campus, Ryan Johnson, Sonya Shepherd, A. Mccrory

Sonya S. Gaither

No abstract provided.

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Timing And Extent Of Late Quaternary Paleolakes In The Trans-Pecos Closed Basin, West Texas And South-Central New Mexico, David Wilkins, Donald Currey Apr 1997

Timing And Extent Of Late Quaternary Paleolakes In The Trans-Pecos Closed Basin, West Texas And South-Central New Mexico, David Wilkins, Donald Currey

David E. Wilkins

The Trans-Pecos Closed Basin is a hydrographically closed region covering 20,000 km centered on Salt Basin, 160 km east of El Paso, Texas. Geomorphic and limnetic evidence have been used to identify four major highstands for Lake King during the last glacial maximum (LGM). Additional geomorphic features from a second, recently identified, paleolake, Lake Sacramento, have been found in the Beargrass subbasin, a nested subbasin approximately 75 km northwest of Salt Basin. Radiocarbon ages of the organic material in Lake King sediments date four abrupt climate changes and rapid lacustrine transgressions during the LGM with a quasi-periodicity of 2000 yr. …

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Neuroendocrine Aspects Of Primary Endogenous Depression Xv. Mathematical Modeling Of Nocturnal Melatonin Secretion In Major Depressives And Normal Controls, L. Kathleen Sekula, Joseph F. Lucke, E. Kevin Heist, R. Kenneth Czambel, Robert T. Rubin Jan 1997

Neuroendocrine Aspects Of Primary Endogenous Depression Xv. Mathematical Modeling Of Nocturnal Melatonin Secretion In Major Depressives And Normal Controls, L. Kathleen Sekula, Joseph F. Lucke, E. Kevin Heist, R. Kenneth Czambel, Robert T. Rubin

Joseph Lucke

We previously reported a trend toward a higher mean nocturnal serum melatonin (MEL) concentration, based on 30-min blood sampling over 24 h, in 23 female definite endogenous depressives compared to 23 matched normal female control subjects, and no significant difference in 15 male depressives compared to their controls (Rubin et al., 1992). In both groups of patients vs. their controls, there also were trends toward an earlier MEL rise time, by about 30 min, and a later MEL peak time, by about 90 min. Because the offset of MEL secretion was not estimated in that study, the total duration of …

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Uniformly Adaptive Estimation For Models With Arma Errors, Douglas Steigerwald Dec 1996

Uniformly Adaptive Estimation For Models With Arma Errors, Douglas Steigerwald

Douglas G. Steigerwald

A semiparametric estimator based on an unknown density is uniformly adaptive if the expected loss of the estimator converges to the asymptotic expected loss of the maximum likelihood estimator based on the true density (MLE), and if convergence does not depend on either the parameter values or the form of the unknown density. Without uniform adaptivity, the asymptotic expected loss of the MLE need not approximate the expected loss of a semiparamteric estimator for any finite sample. I show that a two-step semiparametric estimator is uniformly adaptive for the parameters of nonlinear regression models with autoregressive moving average errors.

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Econometric Estimation Of Foresight: Tax Policy And Investment In The U.S., Douglas G. Steigerwald, Charles Stuart Dec 1996

Econometric Estimation Of Foresight: Tax Policy And Investment In The U.S., Douglas G. Steigerwald, Charles Stuart

Douglas G. Steigerwald

We develop a method for measuring the foresight agents have. We first dichotomize an agent's information at current date t into knowledge up to date t+f and expectations after t+f. We then form a residual-based test statistic that allows us to compare prediction errors for econometric models based on different values of f. We illustrate the method, examining investment around tax reforms to measure the foresight firms have about tax policy. In this illustration, current investment appears to reflect currently available information but little foresight other than foresight of enacted policy changes.

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Asymptotic Bias For Quasi-Maximum Likelihood Estimators In Models With Conditional Heteroskedasticity, Douglas G. Steigerwald, Whitney Newey Dec 1996

Asymptotic Bias For Quasi-Maximum Likelihood Estimators In Models With Conditional Heteroskedasticity, Douglas G. Steigerwald, Whitney Newey

Douglas G. Steigerwald

Virtually all applications of time-varying conditional variance models use a quasi-maximum likelihood estimator (QMLE). Consistency of a QMLE requires an identification condition that the quasi-log-likelihood have a unique maximum at the true conditional mean and relative scale parameters. We show that the identification condition holds for a non-Gaussian QMLE if the conditional mean is identically zero or if a symmetry condition is satisfied. Without symmetry an additional parameter, for the location of the innovation density, must be added for consistency. We calculate the efficiency loss from adding such a parameter under symmetry, when the parameter is not needed. We also …

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Aphasic Sentence Comprehension As A Resource Deficit: A Computational Approach, Henk J. Haarmann, Marcel Adam Just, Patricia A. Carpenter Dec 1996

Aphasic Sentence Comprehension As A Resource Deficit: A Computational Approach, Henk J. Haarmann, Marcel Adam Just, Patricia A. Carpenter

Marcel Adam Just

No abstract provided.

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