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Physical Sciences and Mathematics

2004

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The Icdm Development Toolkit: Technical Description, Russell Leighton, Lakshmi Vempati, Alan Davis, Mark Porczak, Jens G. Pohl Dec 2004

The Icdm Development Toolkit: Technical Description, Russell Leighton, Lakshmi Vempati, Alan Davis, Mark Porczak, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

This report provides a technical description of the Integrated Cooperative Decision-Making (ICDM) software toolkit for the development of intelligent decision-support applications. An overview of the transformational forces that have precipitated the need for a development toolkit capable of supporting a distributed, information-centric software environment, and the objectives of ICDM are contained in a companion CDM Technical Report (CDM-16-04) entitled: “The ICDM Development Toolkit: Purpose and Overview”.

ICDM is an application development framework and toolkit for distributed decision-support systems incorporating software agents that collaborate with each other and human users to monitor changes (i.e., events) in the state of problem situations, …


Ranking Usrds Provider-Specific Smrs From 1998-2001, Rongheng Lin, Thomas A. Louis, Susan M. Paddock, Greg Ridgeway Dec 2004

Ranking Usrds Provider-Specific Smrs From 1998-2001, Rongheng Lin, Thomas A. Louis, Susan M. Paddock, Greg Ridgeway

Johns Hopkins University, Dept. of Biostatistics Working Papers

Provider profiling (ranking, "league tables") is prevalent in health services research. Similarly, comparing educational institutions and identifying differentially expressed genes depend on ranking. Effective ranking procedures must be structured by a hierarchical (Bayesian) model and guided by a ranking-specific loss function, however even optimal methods can perform poorly and estimates must be accompanied by uncertainty assessments. We use the 1998-2001 Standardized Mortality Ratio (SMR) data from United States Renal Data System (USRDS) as a platform to identify issues and approaches. Our analyses extend Liu et al. (2004) by combining evidence over multiple years via an AR(1) model; by considering estimates …


Semi-Parametric Single-Index Two-Part Regression Models, Xiao-Hua Zhou, Hua Liang Dec 2004

Semi-Parametric Single-Index Two-Part Regression Models, Xiao-Hua Zhou, Hua Liang

UW Biostatistics Working Paper Series

In this paper, we proposed a semi-parametric single-index two-part regression model to weaken assumptions in parametric regression methods that were frequently used in the analysis of skewed data with additional zero values. The estimation procedure for the parameters of interest in the model was easily implemented. The proposed estimators were shown to be consistent and asymptotically normal. Through a simulation study, we showed that the proposed estimators have reasonable finite-sample performance. We illustrated the application of the proposed method in one real study on the analysis of health care costs.


Adaptation And Sustainability In A Small Arctic Community: Results Of An Agent-Based Simulation Model, Matthew Berman, Craig Nicolson, Gary Kofinas, Joe Tetlichi, Stephanie Martin Dec 2004

Adaptation And Sustainability In A Small Arctic Community: Results Of An Agent-Based Simulation Model, Matthew Berman, Craig Nicolson, Gary Kofinas, Joe Tetlichi, Stephanie Martin

Craig Nicolson

Climate warming and resource development could alter key Arctic ecosystem functions that support fish and wildlife resources harvested by local indigenous communities. A different set of global forces—government policies and tourism markets—increasingly directs local cash economies that communities use to support subsistence activities. Agent-based computational models (ABMs) contribute to an integrated assessment of community sustainability by simulating how people interact with each other and adapt to changing economic and environmental conditions. Relying on research and local knowledge to provide rules and parameters for individual and collective decision making, our ABM generates hypothetical social histories as adaptations to scenario-driven changes in …


Risk Perceptions Of Adults In The Town Of Unicoi, Tennessee, Regarding The Possible Building Of A Uranium Enrichment Plant., Shannon Kathleen Sellards Dec 2004

Risk Perceptions Of Adults In The Town Of Unicoi, Tennessee, Regarding The Possible Building Of A Uranium Enrichment Plant., Shannon Kathleen Sellards

Electronic Theses and Dissertations

A prolonged siting controversy for a uranium enrichment facility has occurred in the Town of Unicoi, Tennessee. One hundred-seventy residents of Unicoi were interviewed using a questionnaire regarding the building of a proposed uranium enrichment facility for Unicoi. The questionnaire sought to determine relationships between residents’ risk perceptions and 18 variables. When the Fisher’s exact procedure was applied at α< 0.05, the results indicated several associations. Odds ratio measured the strength of association. Results are reported as crude measures of association. Risk perceptions were influenced by the choice of possible locations for the facility [p=0.0003; OR=32.6]. Residents' risk perceptions were associated with a history of working with nuclear materials [p=0.0476; OR=3.2]. Finally, risk perceptions were associated with residents' beliefs that the nuclear facility would affect their health [p=0.0001; OR=18.8]. These results are discussed in light of risk perception and communication theories.


Estimating The Economic Recreational Value Of Paracas National Reserve In Ica Peru: A Fair Fee Implementation Approach, Jaqueline Garcia-Yi Dec 2004

Estimating The Economic Recreational Value Of Paracas National Reserve In Ica Peru: A Fair Fee Implementation Approach, Jaqueline Garcia-Yi

Electronic Theses and Dissertations

Paracas National Reserve (PNR) is one of the fifty-seven protected areas that belong to the National System of Protected Areas (SINANPE) of Peru. Located in Ica Department, on the Pacific coast of Peru, it is the only coastal-marine ecosystem currently protected by the Peruvian government. PNR has been internationally recognized, principally as a wintering area for bird migrations. It has been designated as a Regional Shorebird Reserve by the Western Hemisphere Shorebird Reserve Network (1991), a Ramsar site by the Ramsar Convention on Wetlands of International Importance Especially as Waterfowl Habitat (1992), and a Particular Sensitive Sea Area by the …


Genetic Methods Improve Accuracy Of Gender Determination In Beavers, Christen Lenney Williams, Stewart W. Breck, Bruce W. Baker Dec 2004

Genetic Methods Improve Accuracy Of Gender Determination In Beavers, Christen Lenney Williams, Stewart W. Breck, Bruce W. Baker

United States Department of Agriculture Wildlife Services: Staff Publications

Gender identification of sexually monomorphic mammals can be difficult. We used analysis of zinc-finger protein (Zfx and Zfy) DNA regions to determine gender of 96 beavers (Castor canadensis) from 3 areas and used these results to verify gender determined in the field. Gender was correctly determined for 86 (89.6%) beavers. Incorrect assignments were not attributed to errors in any one age or sex class. Although methods that can be used in the field (such as morphological methods) can provide reasonably accurate gender assignments in beavers, the genetic method might be preferred in certain situations.


Preparation And Electrochemical Magnesium Insertion Behaviors Of Mgv_2o_6, Hua-Tang Yuan, Li-Fang Jiao, Jian-Sheng Cao, Xiu-Sheng Liu, Ming Zhao, Yong-Mei Wang Nov 2004

Preparation And Electrochemical Magnesium Insertion Behaviors Of Mgv_2o_6, Hua-Tang Yuan, Li-Fang Jiao, Jian-Sheng Cao, Xiu-Sheng Liu, Ming Zhao, Yong-Mei Wang

Journal of Electrochemistry

MgV_2O_6was synthesized by conventional solid-state reaction from MgO and V_2O_(5)as starting materials. X-Ray diffraction analysis showed that the prepared sample belongs to the monoclinic structure. Electrochemical magnesium insertion from aprotic electrolytes such as organomagnesium halides into this host was found possible and exhibited charge/discharge circulation.


Automating The Extraction Of Domain-Specific Information From The Web-A Case Study For The Genealogical Domain, Troy L. Walker Nov 2004

Automating The Extraction Of Domain-Specific Information From The Web-A Case Study For The Genealogical Domain, Troy L. Walker

Theses and Dissertations

Current ways of finding genealogical information within the millions of pages on the Web are inadequate. In an effort to help genealogical researchers find desired information more quickly, we have developed GeneTIQS, a Genealogy Target-based Information Query System. GeneTIQS builds on ontology-based methods of data extraction to allow database-style queries on the Web. This thesis makes two main contributions to GeneTIQS. (1) It builds a framework to do generic ontology-based data extraction. (2) It develops a hybrid record separator based on Vector Space Modeling that uses both formatting clues and data clues to split pages into component records. The record …


How (West) Hollywood Adds Up: A Queer Theoretical View Of Mathematics And Mathematicians In Film, Christopher D. Goff Nov 2004

How (West) Hollywood Adds Up: A Queer Theoretical View Of Mathematics And Mathematicians In Film, Christopher D. Goff

College of the Pacific Faculty Presentations

No abstract provided.


Modeling Incomplete Longitudinal Data, Hakan Demirtas Nov 2004

Modeling Incomplete Longitudinal Data, Hakan Demirtas

Journal of Modern Applied Statistical Methods

This article presents a review of popular parametric, semiparametric and ad-hoc approaches for analyzing incomplete longitudinal data.


Statistics And Technology: Reflections On 35 Years Of Change, James J. Higgins Nov 2004

Statistics And Technology: Reflections On 35 Years Of Change, James J. Higgins

Journal of Modern Applied Statistical Methods

From the days when statistical calculations were done on mechanical calculators to today, technology has transformed the discipline of statistics. More than just giving statisticians the power to crunch numbers, it has fundamentally changed the way we teach, do research, and consult. In this article, I give some examples of this from my 35 years as an academic statistician.


A Modification Of The Em Algorithm To Estimate An Andersen-Gill Gamma Frailty Model For Multivariate Failure Time Data, Maria Antònia Barceló, Marc Saez Nov 2004

A Modification Of The Em Algorithm To Estimate An Andersen-Gill Gamma Frailty Model For Multivariate Failure Time Data, Maria Antònia Barceló, Marc Saez

Journal of Modern Applied Statistical Methods

A modification of the Andersen-Gill gamma shared frailty model is presented. The variance of the frailty is directly modeled by means of a generalized linear model, the EM algorithm is modified in order to simultaneously estimate a semiparametric model for the failure times and a model for the variance of the frailty. A simulation study is conducted to evaluate the performance of the proposed algorithm (EMB algorithm) and compared with other methods, a marginal model, and a conditional model. Multivariate data from a nosocomial infection study is used to illustrate the methods. The EMB fit turned out to be better …


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 21, Number 3, November 2004, College Of Engineering And Computer Science, Wright State University Nov 2004

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 21, Number 3, November 2004, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.


Using Genetic Analyses To Identify Predators, C. L. Williams, J. J. Johnston Oct 2004

Using Genetic Analyses To Identify Predators, C. L. Williams, J. J. Johnston

Sheep and Goat Research Journal

Coyote and dog depredation account for much of the economic losses to livestock in the United States (National Agricultural Statistical Service, 2000, 2001). However, depredation by other species (such as members of reintroduced wolf populations) can be more socially and politically contentious. Predators are often elusive and attacks on livestock are not often witnessed but the species of predator causing stock losses can sometimes be ascertained from evidence near the carcass (such as scat or hair), the attack pattern, or size and spacing of bite wounds. However, these species assignments can be subjective and may be influenced by the experience …


Tme Volume 1, Number 2 Oct 2004

Tme Volume 1, Number 2

The Mathematics Enthusiast

No abstract provided.


Water Current, Volume 36, No. 4. Fall 2004 Oct 2004

Water Current, Volume 36, No. 4. Fall 2004

Water Current Newsletter

Contents

• Gleick to Speak at April Water Law Science and Policy Conference by Steve Ress

• Measurements From Nearly 5,000 Wells Show Groundwater Declines by Steve Ress

• From the Director

• Meet the Faculty

• Combating An Odorless, Tasteless, Unseen Problem in Nebraska Drinking Water by Steve Ress

• UNL Researchers Studying SDI Technology Near Clay Center by Steve Ress

• UNL Study Looks at Economic Impacts of Water Allocations To Republican River Basin Economy

• Husker Harvest Days 2004

• Algae Test Kits Travel Far and Wide

• Missouri River Study Nets EPA Grant

• Free Lectures …


The Nature Of Proof In Today's Classroom. Book Review Of The Nature Of Proof, Erica Lane Oct 2004

The Nature Of Proof In Today's Classroom. Book Review Of The Nature Of Proof, Erica Lane

The Mathematics Enthusiast

Harold Fawcett. The Nature of Proof. New York City: Bureau of Publications, Columbia University, 1938. Re-printed by the National Council of Teachers of Mathematics in 1995.

Throughout the world, children are taught new ideas and concepts in a variety of ways, and the advocates of the different approaches claim that their method is the most effective and profitable for the students. In addition to the different teaching styles, each individual learns the material in a distinct manner. Teachers, therefore, must be aware of the diverse techniques of both teaching and learning in an effort to optimize the learning experience …


Use Of Fecal Glucocorticoid Metabolite Measures In Conservation Biology Research: Considerations For Application And Interpretation, Joshua J. Millspaugh, Brian E. Washburn Sep 2004

Use Of Fecal Glucocorticoid Metabolite Measures In Conservation Biology Research: Considerations For Application And Interpretation, Joshua J. Millspaugh, Brian E. Washburn

United States Department of Agriculture Wildlife Services: Staff Publications

Fecal glucocorticoid metabolite analyses are increasingly being used by a variety of scientists (e.g., conservation biologists, animal scientists) to examine glucocorticoid (i.e., stress hormone) secretion in domestic and wild vertebrates. Adrenocortical activity (i.e., stress response) is of interest to conservation biologists because stress can alter animal behavior, reduce resistance to disease, and affect population performance. The noninvasiveness of fecal-based assessments is attractive, particularly when studying endangered species, because samples can often be obtained without disturbing the animal. Despite such advantages, many confounding factors inhibit the utility of this technique in addressing conservation problems. In particular, interpretation of fecal glucocorticoid metabolite …


Databases For Interval Probabilities, Wenzhong Zhao, Alex Dekhtyar, Judy Goldsmith Sep 2004

Databases For Interval Probabilities, Wenzhong Zhao, Alex Dekhtyar, Judy Goldsmith

Computer Science and Software Engineering

We present a database framework for the efficient storage and manipulation of interval probability distributions and their associated information. Although work on interval probabilities and on probabilistic databases has appeared before, ours is the first to combine these into a coherent and mathematically sound framework including both standard relational queries and queries based on probability theory. In particular, our query algebra allows users not only to query existing interval probability distributions, but also to construct new ones by means of conditionalization and marginalization, as well as other more common database operations.


Psychological Factors Associated With Anticipatory Nausea And Vomiting, Melinda L. Nielsen Sep 2004

Psychological Factors Associated With Anticipatory Nausea And Vomiting, Melinda L. Nielsen

Loma Linda University Electronic Theses, Dissertations & Projects

Many cancer patients experience adverse chemotherapy-related side effects. The present study examined the relationships among disease variables (i.e. stage of cancer, type of breast cancer), medical treatment variables (i.e. toxicity of chemotherapy regimen, strength of antiemetic treatment), psychological variables (i.e. health locus of control, anxiety sensitivity, desire for control, coping strategies), and anticipatory nausea and vomiting in women with breast cancer. One hundred women with breast cancer completed the Multidimensional Health Locus of Control Scale - Form C, the Anxiety Sensitivity Index, the Krantz Health Opinion Survey, the Coping Inventory for Stressful Situations, and the Morrow Assessment of Nausea and …


Prevalence Of Degenerative Joint Disease In A Pre-Orthodontic Adolescent Sample, Marie Mansour Sep 2004

Prevalence Of Degenerative Joint Disease In A Pre-Orthodontic Adolescent Sample, Marie Mansour

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this research was to determine a prevalence of degenerative joint disease in our pre-orthodontic adolescent patients age ten through seventeen. The prevalence was assessed according to gender. Severity of DJD was established for each patient and a "red flag" for diagnosis was identified. The purpose was also to establish norms for joint space for patients with and without degenerative joint disease. Correlations to distal condyle position and angle classification were described. 123 consecutive patients, 77 female and 46 male T1 NewTom records were reviewed. Severity of DJD was classified according to none, mild, moderate, and severe. Sagittal …


Modeling Usage Of An Online Research Community, Yi Zhang Aug 2004

Modeling Usage Of An Online Research Community, Yi Zhang

Dissertations

Although online communities have been thought of as a new way for collaboration across geographic boundaries in the scientific world, they have a problem attracting people to keep visiting. The main purpose of this study is to understand how people behave in such communities, and to build and evaluate tools to stimulate engagement in a research community. These tools were designed based on a research framework of factors that influence online participation and relationship development.

There are two main objectives for people to join an online community, information sharing and interpersonal relationship development, such as friends or colleagues. The tools …


Studying Effects Of Primary Care Physicians And Patients On The Trade-Off Between Charges For Primary Care And Specialty Care Using A Hierarchical Multivariate Two-Part Model, John W. Robinson, Scott L. Zeger, Christopher B. Forrest Aug 2004

Studying Effects Of Primary Care Physicians And Patients On The Trade-Off Between Charges For Primary Care And Specialty Care Using A Hierarchical Multivariate Two-Part Model, John W. Robinson, Scott L. Zeger, Christopher B. Forrest

Johns Hopkins University, Dept. of Biostatistics Working Papers

Objective. To examine effects of primary care physicians (PCPs) and patients on the association between charges for primary care and specialty care in a point-of-service (POS) health plan.

Data Source. Claims from 1996 for 3,308 adult male POS plan members, each of whom was assigned to one of the 50 family practitioner-PCPs with the largest POS plan member-loads.

Study Design. A hierarchical multivariate two-part model was fitted using a Gibbs sampler to estimate PCPs' effects on patients' annual charges for two types of services, primary care and specialty care, the associations among PCPs' effects, and within-patient associations between charges for …


A Hierarchical Multivariate Two-Part Model For Profiling Providers' Effects On Healthcare Charges, John W. Robinson, Scott L. Zeger, Christopher B. Forrest Aug 2004

A Hierarchical Multivariate Two-Part Model For Profiling Providers' Effects On Healthcare Charges, John W. Robinson, Scott L. Zeger, Christopher B. Forrest

Johns Hopkins University, Dept. of Biostatistics Working Papers

Procedures for analyzing and comparing healthcare providers' effects on health services delivery and outcomes have been referred to as provider profiling. In a typical profiling procedure, patient-level responses are measured for clusters of patients treated by providers that in turn, can be regarded as statistically exchangeable. Thus, a hierarchical model naturally represents the structure of the data. When provider effects on multiple responses are profiled, a multivariate model rather than a series of univariate models, can capture associations among responses at both the provider and patient levels. When responses are in the form of charges for healthcare services and sampled …


46th Rocky Mountain Conference On Analytical Chemistry Aug 2004

46th Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 46th annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-endorsed by the Colorado Section of the American Chemical Society and the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Denver, Colorado, August 1-5, 2004.


A Comparative Study Of Interrater Reliability Coefficients Obtained From Different Statistical Procedures Using Monte Carlo Simulation Techniques, Ebrima Nying Aug 2004

A Comparative Study Of Interrater Reliability Coefficients Obtained From Different Statistical Procedures Using Monte Carlo Simulation Techniques, Ebrima Nying

Dissertations

Reliability estimation is a key research component within the global area of educational assessment. The literature reports numerous studies using different statistical techniques for estimating reliability of educational measures. However, few have focused on the estimation of interrater reliability of performance assessment (Abedi, Baker, & Herl, 1995). Specifically, this study compared three different methods for estimating interrater reliability to determine if there are differences among these estimates as a function of: sample size, measurement scale, number of raters and the theoretical population reliability (rho). The three methods of estimation were the Intraclass Correlation (ICC(2, k )) (Shrout & Fleiss, 1979), …


Inside Unlv, Cate Weeks, Carol C. Harter, Diane Russell, Holly Ivy De Vore Aug 2004

Inside Unlv, Cate Weeks, Carol C. Harter, Diane Russell, Holly Ivy De Vore

Inside UNLV

No abstract provided.


Pastoral Risk Management In Southern Ethiopia: Observations From Pilot Projects Based On Participatory Community Assessments, D. Layne Coppock, Solomon Desta, Seyoum Tezera, Rancis K. Lelo Aug 2004

Pastoral Risk Management In Southern Ethiopia: Observations From Pilot Projects Based On Participatory Community Assessments, D. Layne Coppock, Solomon Desta, Seyoum Tezera, Rancis K. Lelo

Environment and Society Faculty Publications

The Borana pastoral system has come under increasing pressure as human populations grow and per capita availability of resources declines. Livestock exhibit large, periodic die-offs that threaten wealth accumulation and food security. Several types of interventions may improve risk management here. For example, there may be opportunity for some pastoralists to diversify their livelihoods. Here we report on a community-based process involving pilot projects begun since 2000. We have embraced Participatory Rural Appraisal (PRA) and Action Research (AR) as tools for investigation and empowerment of local people. Full PRAs were conducted for semi-settled communities, located near towns, to identify priority …


Instructing Teachers Of Children With Disabilities Within The Church Of Jesus Christ Of Latter-Day Saints, Katie E. Sampson Aug 2004

Instructing Teachers Of Children With Disabilities Within The Church Of Jesus Christ Of Latter-Day Saints, Katie E. Sampson

Theses and Dissertations

This study investigates benefits of in-service training on LDS primary teachers' ability to state an objective, obtain and keep attention, use wait time, incorporate active participation, teach to the multiple intelligences, and employ positive behavior management techniques. Two groups of 30 viewed either a video-tape or read a handout. Pre and post surveys were used to determine mean gain.
Using an ANCOVA, comparisons were made of overall mean gain for each group. Results showed participants made a gain of approximately 1/2 point per question on a 4-point scale on the video and the handout (video gain = .6032 p<.01; handout gain = .6264 p<.01). The results of this study support the hypothesis that teachers receiving one in-service will increase their perception of their ability to teach students with special needs.