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2003

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Articles 2701 - 2730 of 3876

Full-Text Articles in Physical Sciences and Mathematics

Spectral Functions Of The Falicov-Kimball Model With Electronic Ferroelectricity, Wei-Guo Yin, Wai-Ning Mei, Chun-Gang Duan, Hai-Qing Lin, John R. Hardy Jan 2003

Spectral Functions Of The Falicov-Kimball Model With Electronic Ferroelectricity, Wei-Guo Yin, Wai-Ning Mei, Chun-Gang Duan, Hai-Qing Lin, John R. Hardy

Physics Faculty Publications

We calculate the angular resolved photoemission spectrum of the Falicov-Kimball model with electronic ferroelectricity where d- and f-electrons have different hoppings. In mix-valence regimes, the presence of strong scattering processes between df excitons and a hole, created by emission of an electron, leads to the formation of pseudospin polarons and novel electronic structures with bandwidth scaling with that of df excitons. Especially, in the two-dimensional case, we find that flat regions exist near the bottom of the quasiparticle band in a wide range of the d- and f-level energy difference.


A Direct Simulation Monte Carlo Method For The Uehling-Uhlenbeck-Boltzmann Equation, Alejandro Garcia, Wolfgang Wagner Jan 2003

A Direct Simulation Monte Carlo Method For The Uehling-Uhlenbeck-Boltzmann Equation, Alejandro Garcia, Wolfgang Wagner

Alejandro Garcia

In this paper we describe a direct simulation Monte Carlo algorithm for the Uehling-Uhlenbeck-Boltzmann equation in terms of Markov processes. This provides a unifying framework for both the classical Boltzmann case as well as the Fermi-Dirac and Bose-Einstein cases. We establish the foundation of the algorithm by demonstrating its link to the kinetic equation. By numerical experiments we study its sensitivity to the number of simulation particles and to the discretization of the velocity space, when approximating the steady-state distribution.


Inverted Velocity Profile In The Cylindrical Couette Flow Of A Rarefied Gas, Alejandro Garcia, K. Aoki, H. Yoshida, T. Nakanishi Jan 2003

Inverted Velocity Profile In The Cylindrical Couette Flow Of A Rarefied Gas, Alejandro Garcia, K. Aoki, H. Yoshida, T. Nakanishi

Alejandro Garcia

The cylindrical Couette flow of a rarefied gas is investigated, under the diffuse-specular reflection condition of Maxwell’s type on the cylinders, in the case where the inner cylinder is rotating whereas the outer cylinder is at rest. The inverted velocity profile for small accommodation coefficients, pointed out by Tibbs, Baras, and Garcia [Phys. Rev. E 56, 2282 (1997)] on the basis of a Monte Carlo simulation, is investigated extensively by means of a systematic asymptotic analysis for small Knudsen numbers as well as the direct numerical analysis of the Boltzmann equation, and the parameter range in which the phenomenon appears …


A Dearth Of Dark Matter In Ordinary Elliptical Galaxies, Aaron J. Romanowsky, N. G. Douglas, M. Arnaboldi, K. Kuijken, M. R. Merrifield, N. R. Napolitano, M. Capaccioli Jan 2003

A Dearth Of Dark Matter In Ordinary Elliptical Galaxies, Aaron J. Romanowsky, N. G. Douglas, M. Arnaboldi, K. Kuijken, M. R. Merrifield, N. R. Napolitano, M. Capaccioli

Aaron J. Romanowsky

The kinematics of the outer parts of three intermediate-luminosity elliptical galaxies were studied with the Planetary Nebula Spectrograph. The galaxies' velocity-dispersion profiles were found to decline with the radius, and dynamical modeling of the data indicates the presence of little if any dark matter in these galaxies' halos. This unexpected result conflicts with findings in other galaxy types and poses a challenge to current galaxy formation theories.


Tracing The Star Stream Through M31 Using Planetary Nebula Kinematics, H. R. Merrett, K. Kuijken, M. R. Merrifield, Aaron J. Romanowsky, N. G. Douglas, N. R. Napolitano, M. Arnaboldi, M. Capaccioli, K. C. Freeman, O. Gerhard, N. W. Evans, M. I. Wilkinson, C. Halliday, T. J. Bridges, D. Carter Jan 2003

Tracing The Star Stream Through M31 Using Planetary Nebula Kinematics, H. R. Merrett, K. Kuijken, M. R. Merrifield, Aaron J. Romanowsky, N. G. Douglas, N. R. Napolitano, M. Arnaboldi, M. Capaccioli, K. C. Freeman, O. Gerhard, N. W. Evans, M. I. Wilkinson, C. Halliday, T. J. Bridges, D. Carter

Aaron J. Romanowsky

We present a possible orbit for the Southern Stream of stars in M31, which connects it to the Northern Spur. Support for this model comes from the dynamics of planetary nebulae (PNe) in the disc of M31: analysis of a new sample of 2611 PNe obtained using the Planetary Nebula Spectrograph reveals ∼20 objects with kinematics inconsistent with the normal components of the galaxy, but which lie at the right positions and velocities to connect the two photometric features via this orbit. The satellite galaxy M32 is coincident with the stream both in position and velocity, adding weight to the …


Small Heat-Shock Proteins And Clusterin: Intra- And Extracellular Molecular Chaperones With A Common Mechanism Of Action And Function, J. A. Carver, A. Rekas, D. C. Thorn, M. R. Wilson Jan 2003

Small Heat-Shock Proteins And Clusterin: Intra- And Extracellular Molecular Chaperones With A Common Mechanism Of Action And Function, J. A. Carver, A. Rekas, D. C. Thorn, M. R. Wilson

Faculty of Science - Papers (Archive)

Small heat-shock proteins (sHsps) and clusterin are molecular chaperones that share many functional similarities despite their lack of significant sequence similarity. These functional similarities, and some differences, are discussed. sHsps are ubiquitous intracellular proteins whereas clusterin is generally found extracellularly. Both chaperones potently prevent the amorphous aggregation and precipitation of target proteins under stress conditions such as elevated temperature, reduction and oxidation. In doing so, they act on the slow off-folding protein pathway. The conformational dynamism and aggregated state of both proteins may be crucial for their chaperone function. Subunit exchange is likely to be important in regulating chaperone action; …


Environmental (Re)Education And Local Environmental Knowledge: Statutory Ground-Based Monitoring And Pastoral Culture In Central Australia, Nicholas J. Gill Jan 2003

Environmental (Re)Education And Local Environmental Knowledge: Statutory Ground-Based Monitoring And Pastoral Culture In Central Australia, Nicholas J. Gill

Faculty of Science - Papers (Archive)

Ground-based monitoring of rangeland condition is common in Australian pastoral administration systems. In the Northern Territory, such monitoring is officially seen as a key plank of sustainable pastoral land use. In the NT and elsewhere, these monitoring schemes have sought to increase participation by pastoralists. Involvement of pastoralists in monitoring is theoretically an educative process that will cause pastoralists to more critically examine their management practices. Critical perspectives on the relationship between rangelands science/extension and pastoralist knowledge systems and concerns, however, suggest that pastoralists’ reception of such monitoring schemes will be influenced by a range of social contexts, including the …


Stemocurtisine, The First Pyrido[1,2-A]Azapine Stemona Alkaloid, Pitchaya Mungkornasawakul, Stephen G. Pyne, Araya Jatisatienr, Damrat Supyen, Wilford Lie, Alison T. Ung, Brian W. Skelton, Allan H. White Jan 2003

Stemocurtisine, The First Pyrido[1,2-A]Azapine Stemona Alkaloid, Pitchaya Mungkornasawakul, Stephen G. Pyne, Araya Jatisatienr, Damrat Supyen, Wilford Lie, Alison T. Ung, Brian W. Skelton, Allan H. White

Faculty of Science - Papers (Archive)

A new pentacyclic stemona alkaloid, stemocurtisine (2), with a novel pyrido[1,2-a]azapine A,B-ring system, has been isolated from a root extract of Stemona curtisii. The structure and relative stereochemistry was determined by spectral data interpretation and X-ray crystallography.


Spatial Statistics In The Presence Of Location Error With An Application To Remote Sensing Of The Environment, Noel A. Cressie, John Kornak Jan 2003

Spatial Statistics In The Presence Of Location Error With An Application To Remote Sensing Of The Environment, Noel A. Cressie, John Kornak

Faculty of Informatics - Papers (Archive)

Techniques for the analysis of spatial data have, to date, tended to ignore any effect caused by error in specifying the spatial locations at which measurements are recorded. This paper reviews the methods for adjusting spatial inference in the presence of data-location error, particularly for data that. have a continuous spatial index (geostatistical data). New kriging equations are developed and evaluated based on a simulation experiment. They are also applied to remote-sensing data from the Total Ozone Mapping Spectrometer instrument on the Nimbus-7 satellite, where the location error is caused by assignment of the data to their nearest grid-cell centers. …


2,5-Di-2-Thienylthiazolo[4,5-D]Thiazole, Pawel Wagner, Maciej Kubicki Jan 2003

2,5-Di-2-Thienylthiazolo[4,5-D]Thiazole, Pawel Wagner, Maciej Kubicki

Australian Institute for Innovative Materials - Papers

The mol­ecules of the title compound, C12H6N2S4, lie on centres of symmetry. The thio­phene and thia­zole rings are almost planar and their planes make a dihedral angle of 1.68 (8)°. In the crystal structure, there is a relatively short intermolecular S⋯S contact distance of 3.5786 (9) Å.


Allocating Harmonic Emission To Mv Customers In Long Feeder Systems, D A. Robinson, Victor J. Gosbell Jan 2003

Allocating Harmonic Emission To Mv Customers In Long Feeder Systems, D A. Robinson, Victor J. Gosbell

Faculty of Informatics - Papers (Archive)

Previous work has attempted to find satisfactory methods for the allocation of harmonic current emission MV subsystems containing long feeders. It has been proposed that best use of the network's harmonic absorption capacity is made if the allocated current varies with the inverse square root of the harmonic impedance at the point of connection. It has been shown that an exact solution following this principle requires an impracticably large amount of data. Here it is assumed that each feeder supplied from a given substation has its load distributed uniformly and continuously along it, giving equations requiring only a modest amount …


Preliminary Design Of A High Tc Superconducting Persistent Mode Current Switch, Christopher J. Hawley, Dominic Cuiuri, Steve Gower Jan 2003

Preliminary Design Of A High Tc Superconducting Persistent Mode Current Switch, Christopher J. Hawley, Dominic Cuiuri, Steve Gower

Faculty of Informatics - Papers (Archive)

Persistent Mode Current Switches (PMCS) are made from coils of superconductor that in theory will provide zero conduction losses when closed. By causing a section of the superconductor to leave its superconducting state and become resistive, the switch is effectively opened. There are currently 3 methods to open a PMCS; 1) applying heat, 2) applying a magnetic field or 3) application of current above the critical current (Ic) of the tape. The first two methods are not suitable for power applications as the switching time is too slow. Recent work at the University of Wollongong and in literature has shown …


Advances In The Use Of Neurophysiologycally-Based Fusion For Visualization And Pattern Recognition Of Medical Imagery, Mario Aguilar, Joshua New, Erion Hasanbelliu Jan 2003

Advances In The Use Of Neurophysiologycally-Based Fusion For Visualization And Pattern Recognition Of Medical Imagery, Mario Aguilar, Joshua New, Erion Hasanbelliu

Research, Publications & Creative Work

The ever increasing number of image modalities available to doctors for diagnosis purposes has established an important need to develop techniques that support work-load reduction and information maximization. To this end, we have improved on an image fusion architecture first developed for night vision applications. This technique, presented at Fusion 2002, utilizes 3D operators to combine volumetric image sets while maximizing information content. In our approach, we have combined the use of image fusion and userdefined pattern recognition within a 3D human-computer interface. Here, we present our latest advances towards enhancing information visualization and supporting pattern recognition. We also report …


Dorchester County, Maryland Shoreline Situation Report Methods And Guidelines - Gis Data, Alaude Barbosa, Marcia Berman, Harry Berquist, Sharon Dewing, Carl Hershner, Helen Rea, Tamia Rudnicky, Daniel E. Schatt, David Weiss, Helen Woods Jan 2003

Dorchester County, Maryland Shoreline Situation Report Methods And Guidelines - Gis Data, Alaude Barbosa, Marcia Berman, Harry Berquist, Sharon Dewing, Carl Hershner, Helen Rea, Tamia Rudnicky, Daniel E. Schatt, David Weiss, Helen Woods

Data

The Center for Coastal Resources Management (CCRM) at the Virginia Institute of Marine Science (VIMS) has generated Shoreline Situation Reports (SSRs) for coastal localities in the state of Maryland. This effort compliments a parallel effort in Virginia by the same group. SSRs were developed by VIMS in the 1970s for Virginia and have been the foundation for shoreline management planning in Tidewater Virginia ever since. CCRM has developed new protocols for collecting, disseminating, and reporting data relevant to shoreline management issues using state of the art mapping and remote sensing techniques. New SSRs are being generated on a county by …


Assessment Of Selected Reef Sites In Northern And South-Central Belize, Including Recovery From Bleaching And Hurricane Disturbances (Stony Corals, Algae And Fish), Paulette M. Peckol, H. Allen Curran, Emily Y. Floyd, Martha L. Robbart, Benjamin J. Greenstein, Kate L. Buckman Jan 2003

Assessment Of Selected Reef Sites In Northern And South-Central Belize, Including Recovery From Bleaching And Hurricane Disturbances (Stony Corals, Algae And Fish), Paulette M. Peckol, H. Allen Curran, Emily Y. Floyd, Martha L. Robbart, Benjamin J. Greenstein, Kate L. Buckman

Geosciences: Faculty Publications

The condition of coral. algal. and fish populations in fore reefs. patch reefs, and coral reef ridges was investigated at 13 sites along the northern and south-central Belize barrier reef during May 1999, documenting effects of the 1998 warming episode and Hurricane Mitch. We found high percentages of partial, or even complete, colony mortality of major reef-builders (Acropora palmata, the Montastraea annuluris species complex and Agaricia tenuifolia) that were rarely censused as recruits. A. tenuifolia, formerly a space-dominant coral in reef ridges, had incurred nearly 100% mortality after bleaching. Nearly 45% of the M. annurluris complex …


On The Divergence In The General Sense Of Q-Continued Fractions On The Unit Circle, Douglas Bowman, James Mclaughlin Jan 2003

On The Divergence In The General Sense Of Q-Continued Fractions On The Unit Circle, Douglas Bowman, James Mclaughlin

Mathematics Faculty Publications

We show, for each q-continued fraction G(q) in a certain class of continued fractions, that there is an uncountable set of points on the unit circle at which G(q) diverges in the general sense. This class includes the Rogers-Ramanujan continued fraction and the three Ramanujan-Selberg continued fraction. We discuss the implications of our theorems for the general convergence of other q-continued fractions, for example the G¨ollnitz-Gordon continued fraction, on the unit circle.


Multi-Variable Polynomial Solutions To Pell's Equation And Fundamental Units In Real Quadratic Fields, James Mclaughlin Jan 2003

Multi-Variable Polynomial Solutions To Pell's Equation And Fundamental Units In Real Quadratic Fields, James Mclaughlin

Mathematics Faculty Publications

Solving Pell’s equation is of relevance in finding fundamental units in real quadratic fields and for this reason polynomial solutions are of interest in that they can supply the fundamental units in infinite families of such fields. In this paper an algorithm is described which allows one to construct, for each positive integer n, a finite collection, {Fi}, of multi-variable polynomials (with integral coefficients), each satisfying a multi-variable polynomial Pell’s equation C 2 i − FiH 2 i = (−1)n−1 , where Ci and Hi are multi-variable polynomials with integral coefficients. Each positive integer whose square-root has a regular continued …


Polynomial Solutions To Pell's Equation And Fundamental Units In Real Quadratic Fields, James Mclaughlin Jan 2003

Polynomial Solutions To Pell's Equation And Fundamental Units In Real Quadratic Fields, James Mclaughlin

Mathematics Faculty Publications

Finding polynomial solutions to Pell’s equation is of interest as such solutions sometimes allow the fundamental units to be determined in an infinite class of real quadratic fields. In this paper, for each triple of positive integers (c, h, f) satisfying c 2 − f h2 = 1, where (c, h) are the smallest pair of integers satisfying this equation, several sets of polynomials (c(t), h(t), f(t)) which satisfy c(t) 2 − f(t) h(t) 2 = 1 and (c(0), h(0), f(0)) = (c, h, f) are derived. Moreover, it is shown that the pair (c(t), h(t)) constitute the fundamental polynomial …


Eutrophication And Carbon Sources In Chesapeake Bay Over The Last 2700 Yr: Human Impacts In Context, John F. Bratton, Steven M. Colman, Robert R. Seal, Ii Jan 2003

Eutrophication And Carbon Sources In Chesapeake Bay Over The Last 2700 Yr: Human Impacts In Context, John F. Bratton, Steven M. Colman, Robert R. Seal, Ii

United States Geological Survey: Staff Publications

To compare natural variability and trends in a developed estuary with human-influenced patterns, stable isotope ratios (δ13C and δ15N) were measured in sediments from five piston cores collected in Chesapeake Bay. Mixing of terrestrial and algal carbon sources primarily controls patterns of δ13Corg profiles, so this proxy shows changes in estuary productivity and in delivery of terrestrial carbon to the bay. Analyses of δ15N show periods when oxygen depletion allowed intense denitrification and nutrient recycling to develop in the seasonally stratified water column, in addition to recycling taking place in surficial …


Estimation Of Fishing Tournament Mortality And Its Sampling Variance, Gene R. Wilde, Kevin L. Pope, Richard E. Strauss Jan 2003

Estimation Of Fishing Tournament Mortality And Its Sampling Variance, Gene R. Wilde, Kevin L. Pope, Richard E. Strauss

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The mortality of fish captured in fishing tournaments has commonly been estimated incorrectly and, thus far, only one account has presented an estimate of the standard error or confidence interval for tournament-associated mortality. In this article we describe methods for estimating the initial, delayed, and total mortality of tournament-caught fish and provide formulae for estimating the sampling variances of these estimates. The absence of such estimates from previous studies may explain an observed lack of change in tournament-associated mortality between the 1980s and the 1990s. Our methods provide insight into the design of studies of tournament-associated mortality and suggest, for …


Yellow Jackets May Be An Underestimated Component Of An Ant-Seed Mutualism, Megan T. Bale, Jennifer A. Zettler, Bradford A. Robinson, Timothy P. Spira, Craig R. Allen Jan 2003

Yellow Jackets May Be An Underestimated Component Of An Ant-Seed Mutualism, Megan T. Bale, Jennifer A. Zettler, Bradford A. Robinson, Timothy P. Spira, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Yellow jackets (Hymenoptera: Vespidae) are attracted to the typically ant-dispersed seeds of trilliums and will take seeds from ants in the genus Aphaeogaster. To determine if yellow jacket, Vespulla maculifrons (Buysson), presence interferes with seed foraging by ants, we presented seeds of Trillium discolor Wray to three species (A. texana carolinesis Wheeler, Formica schaufussi Mayr, and Solenopsis invicta Buren) of seed-carrying ants in areas where vespids were present or excluded. We found that interspecific aggression between yellow jackets and ants is species specific. Vespid presence decreased average foraging time and increased foraging efficiency of two of the three …


Ferroelectricity In Free Niobium Clusters, Ramiro Moro, Xiaoshan Xu, Shuangye Yin, Walt A. De Heer Jan 2003

Ferroelectricity In Free Niobium Clusters, Ramiro Moro, Xiaoshan Xu, Shuangye Yin, Walt A. De Heer

Xiaoshan Xu Papers

Electric deflections of gas-phase, cryogenically cooled, neutral niobium clusters [NbN; number of atoms (N) = 2 to 150, temperature (T) = 20 to 300 kelvin], measured in molecular beams, show that cold clusters may attain an anomalous component with very large electric dipole moments. In contrast, room-temperature measurements show normal metallic polarizabilities. Characteristic energies kBTG(N) [Boltzmann constant kB times a transition temperature TG(N)] are identified, below which the ferroelectric-like state develops. Generally, TG decreases [110 > TG(N) > 10K] as …


Benefit-Cost Analysis Of Reproduction-Monitoring And Predator-Removal Variables Associated With Protection Of The Endangered California Least Tern, Stephanie A. Shwiff, Ray T. Sterner, John W. Turman, Brian D. Foster Jan 2003

Benefit-Cost Analysis Of Reproduction-Monitoring And Predator-Removal Variables Associated With Protection Of The Endangered California Least Tern, Stephanie A. Shwiff, Ray T. Sterner, John W. Turman, Brian D. Foster

Wildlife Damage Management Conference Proceedings

The California least tern (Sterna antillarium brownii) is an endangered, small (cm), ground-nesting shorebird that winters along the Pacific Coast of Central America and nests in colonies on coastal dunes and beaches from southern Baja to San Francisco, California. It was one of the originally listed species contained in the Endangered Species Act in 1970. Major nest sites remain at Marine Corps Base Camp Pendleton. During the past 15 years, adult tern counts have increased from about 300 to over 600 breeding pairs at the site. This poster provides results of an empirical analysis of annual fixed-cost agreements …


Ellen G. White And Earth Science, Gerhard Pfandl Jan 2003

Ellen G. White And Earth Science, Gerhard Pfandl

Journal of the Adventist Theological Society

No abstract provided.


Mcnair Research Journal Jan 2003

Mcnair Research Journal

Georgia Southern University McNair Scholars Journal

Full issue of the Georgia Southern University McNair Journal presented by the Ronald E. McNair Post-Baccalaureate Achievement Program at Georgia Southern University.

  • Fifty Years of Brown: An analysis of the impact of Brown on the educational system in Statesboro, Georgia Reece Anthony
  • The Use of Natural Transformation in Actinobacillus pleuropnemoniae to Generate Confirmatory Mutants in a Stereotype 1 Strain Leandra D. Burwell
  • Global outsourcing: A study of attitudes held by Georgia Southern Students Patricia Dugan
  • A Comparison of Theweleit's Red Nurse/White Nurse Figures with the Jezebel/Mammy figures of African Slave Women in the Southern, Ante-Bellum Plantation System Aziza el-Shair
  • The …


Nuclear Genes That Encode Mitochondrial Proteins For Dna And Rna Metabolism Are Clustered In The Arabidopsis Genome, Annakaisa Elo, Anna Lyznik, Delkin O. Gonzalez, Stephen D. Kachman, Sally A. Mackenzie Jan 2003

Nuclear Genes That Encode Mitochondrial Proteins For Dna And Rna Metabolism Are Clustered In The Arabidopsis Genome, Annakaisa Elo, Anna Lyznik, Delkin O. Gonzalez, Stephen D. Kachman, Sally A. Mackenzie

Department of Statistics: Faculty Publications

The plant mitochondrial genome is complex in structure, owing to a high degree of recombination activity that subdivides the genome and increases genetic variation. The replication activity of various portions of the mitochondrial genome appears to be nonuniform, providing the plant with an ability to modulate its mitochondrial genotype during development. These and other interesting features of the plant mitochondrial genome suggest that adaptive changes have occurred in DNA maintenance and transmission that will provide insight into unique aspects of plant mitochondrial biology and mitochondrial- chloroplast coevolution. A search in the Arabidopsis genome for genes involved in the regulation of …


Conjugated Linoleic Acid Does Not Improve Insulin Tolerance In Mice, Kimberly M Hargrave, Michael J. Azain, Stephen D. Kachman, Jess Miner Jan 2003

Conjugated Linoleic Acid Does Not Improve Insulin Tolerance In Mice, Kimberly M Hargrave, Michael J. Azain, Stephen D. Kachman, Jess Miner

Department of Statistics: Faculty Publications

Objective: To determine if the addition or removal of dietary conjugated linoleic acid (CLA) would alter insulin tolerances in mice from two genetic lines.

Research Methods and Procedures: High metabolic rate (MH) and low metabolic rate (ML) mice were assigned to consume 1) a control diet ad libitum, 2) a control diet at a restricted intake, or 3) a diet containing 1% CLA ad libitum. After 9 weeks, an insulin tolerance test was conducted, and a portion of the mice were killed. All remaining mice consumed the control diet ad libitum. Insulin tolerance tests were conducted 11 and 32 days …


Comparing Bayes Model Averaging And Stacking When Model Approximation Error Cannot Be Ignored, Bertrand S. Clarke Jan 2003

Comparing Bayes Model Averaging And Stacking When Model Approximation Error Cannot Be Ignored, Bertrand S. Clarke

Department of Statistics: Faculty Publications

We compare Bayes Model Averaging, BMA, to a non-Bayes form of model averaging called stacking. In stacking, the weights are no longer posterior probabilities of models; they are obtained by a technique based on cross-validation. When the correct data generating model (DGM) is on the list of models under consideration BMA is never worse than stacking and often is demonstrably better, provided that the noise level is of order commensurate with the coefficients and explanatory variables. Here, however, we focus on the case that the correct DGM is not on the model list and may not be well approximated by …


Homogeneous Weights And Exponential Sums, José Felipe Voloch, Judy L. Walker Jan 2003

Homogeneous Weights And Exponential Sums, José Felipe Voloch, Judy L. Walker

Department of Mathematics: Faculty Publications

In this paper, we give a formula as an exponential sum for a homogeneous weight defined by Constantinescu and Heise [3] in the case of Galois rings (or equivalently, rings of Witt vectors) and use this formula to estimate the weight of codes obtained from algebraic geometric codes over rings.


A Tribute To John M. Golden, Chief Ranger Unf Wildlife Sanctuary, Unf Wildlife Sanctuary Jan 2003

A Tribute To John M. Golden, Chief Ranger Unf Wildlife Sanctuary, Unf Wildlife Sanctuary

Faculty and Staff History Printed Materials

A tribute to John M. Golden, Chief Ranger at the UNF Wildlife Sanctuary.