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Full-Text Articles in Categorical Data Analysis

Maximum Likelihood Estimation Of Ordered Multinomial Parameters , Nicholas P. Jewell, Jack Kalbfleisch Oct 2003

Maximum Likelihood Estimation Of Ordered Multinomial Parameters , Nicholas P. Jewell, Jack Kalbfleisch

The University of Michigan Department of Biostatistics Working Paper Series

The pool-adjacent violator-algorithm (Ayer et al., 1955) has long been known to give the maximum likelihood estimator of a series of ordered binomial parameters, based on an independent observation from each distribution (see, Barlow et al., 1972). This result has immediate application to estimation of a survival distribution based on current survival status at a set of monitoring times. This paper considers an extended problem of maximum likelihood estimation of a series of ‘ordered’ multinomial parameters pi = (p1i, p2i, . . . , pmi) for 1 < = I < = k, where ordered means that pj1 < = pj2 < = .. . < = pjk for each j with 1 < = j < = m-1. The data consist of k independent observations X1, . . . ,Xk where Xi has a multinomial distribution with probability parameter pi and known index ni > = 1. By making use of variants of the pool adjacent violator algorithm, …


Cross-Calibration Of Stroke Disability Measures: Bayesian Analysis Of Longitudinal Ordinal Categorical Data Using Negative Dependence, Giovanni Parmigiani, Heidi W. Ashih, Gregory P. Samsa, Pamela W. Duncan, Sue Min Lai, David B. Matchar Aug 2003

Cross-Calibration Of Stroke Disability Measures: Bayesian Analysis Of Longitudinal Ordinal Categorical Data Using Negative Dependence, Giovanni Parmigiani, Heidi W. Ashih, Gregory P. Samsa, Pamela W. Duncan, Sue Min Lai, David B. Matchar

Johns Hopkins University, Dept. of Biostatistics Working Papers

It is common to assess disability of stroke patients using standardized scales, such as the Rankin Stroke Outcome Scale (RS) and the Barthel Index (BI). The Rankin Scale, which was designed for applications to stroke, is based on assessing directly the global conditions of a patient. The Barthel Index, which was designed for general applications, is based on a series of questions about the patient’s ability to carry out 10 basis activities of daily living. As both scales are commonly used, but few studies use both, translating between scales is important in gaining an overall understanding of the efficacy of …


A New Confidence Interval For The Difference Between Two Binomial Proportions Of Paired Data, Xiao-Hua Zhou, Gengsheng Qin Jun 2003

A New Confidence Interval For The Difference Between Two Binomial Proportions Of Paired Data, Xiao-Hua Zhou, Gengsheng Qin

UW Biostatistics Working Paper Series

Motivated by a study on comparing sensitivities and specificities of two diagnostic tests in a paired design when the sample size is small, we first derived an Edgeworth expansion for the studentized difference between two binomial proportions of paired data. The Edgeworth expansion can help us understand why the usual Wald interval for the difference has poor coverage performance in the small sample size. Based on the Edgeworth expansion, we then derived a transformation based confidence interval for the difference. The new interval removes the skewness in the Edgeworth expansion; the new interval is easy to compute, and its coverage …


Supervised Detection Of Regulatory Motifs In Dna Sequences, Sunduz Keles, Mark J. Van Der Laan, Sandrine Dudoit, Biao Xing, Michael B. Eisen May 2003

Supervised Detection Of Regulatory Motifs In Dna Sequences, Sunduz Keles, Mark J. Van Der Laan, Sandrine Dudoit, Biao Xing, Michael B. Eisen

U.C. Berkeley Division of Biostatistics Working Paper Series

Identification of transcription factor binding sites (regulatory motifs) is a major interest in contemporary biology. We propose a new likelihood based method, COMODE, for identifying structural motifs in DNA sequences. Commonly used methods (e.g. MEME, Gibbs sampler) model binding sites as families of sequences described by a position weight matrix (PWM) and identify PWMs that maximize the likelihood of observed sequence data under a simple multinomial mixture model. This model assumes that the positions of the PWM correspond to independent multinomial distributions with four cell probabilities. We address supervising the search for DNA binding sites using the information derived from …


Improved Confidence Intervals For The Sensitivity At A Fixed Level Of Specificity Of A Continuous-Scale Diagnostic Test, Xiao-Hua Zhou, Gengsheng Qin May 2003

Improved Confidence Intervals For The Sensitivity At A Fixed Level Of Specificity Of A Continuous-Scale Diagnostic Test, Xiao-Hua Zhou, Gengsheng Qin

UW Biostatistics Working Paper Series

For a continuous-scale test, it is an interest to construct a confidence interval for the sensitivity of the diagnostic test at the cut-off that yields a predetermined level of its specificity (eg. 80%, 90%, or 95%). IN this paper we proposed two new intervals for the sensitivity of a continuous-scale diagnostic test at a fixed level of specificity. We then conducted simulation studies to compare the relative performance of these two intervals with the best existing BCa bootstrap interval, proposed by Platt et al. (2000). Our simulation results showed that the newly proposed intervals are better than the BCa bootstrap …


New Intervals For The Difference Between Two Independent Binomial Proportions, Xiao-Hua Zhou, Min Tsao, Gengsheng Qin May 2003

New Intervals For The Difference Between Two Independent Binomial Proportions, Xiao-Hua Zhou, Min Tsao, Gengsheng Qin

UW Biostatistics Working Paper Series

In this paper we gave an Edgeworth expansion for the studentized difference of two binomial proportions. We then proposed two new intervals by correcting the skewness in the Edgeworth expansion in a direct and an indirect way. Such the bias-correct confidence intervals are easy to compute, and their coverage probabilities converge to the nominal level at a rate of O(n-½), where n is the size of the combined samples. Our simulation results suggest tat in finite samples the new interval based on the indirect method have the similar performance to the two best existing intervals in terms of coverage accuracy …


Partial Auc Estimation And Regression, Lori E. Dodd, Margaret S. Pepe Jan 2003

Partial Auc Estimation And Regression, Lori E. Dodd, Margaret S. Pepe

UW Biostatistics Working Paper Series

Accurate disease diagnosis is critical for health care. New diagnostic and screening tests must be evaluated for their abilities to discriminate disease from non-diseased states. The partial area under the ROC curve (partial AUC) is a measure of diagnostic test accuracy. We present an interpretation of the partial AUC that gives rise to a new non-parametric estimator. This estimator is more robust than existing estimators, which make parametric assumptions. We show that the robustness is gained with only a moderate loss in efficiency. We describe a regression modelling framework for making inference about covariate effects on the partial AUC. Such …


Census 2000 Demographic Profile Report Of The Older Adult Population In Cuyahoga, Lake, Geauga, Lorain And Medina Counties, Mark Salling, Sharon Bliss, Mcnamara, Brian Jan 2003

Census 2000 Demographic Profile Report Of The Older Adult Population In Cuyahoga, Lake, Geauga, Lorain And Medina Counties, Mark Salling, Sharon Bliss, Mcnamara, Brian

All Maxine Goodman Levin School of Urban Affairs Publications

No abstract provided.


Visualization Methods: A Comparative Study Of New, Traditional And Robust Procedures, Kimberly Crimin Aug 2002

Visualization Methods: A Comparative Study Of New, Traditional And Robust Procedures, Kimberly Crimin

Dissertations

Two major goals in discriminant analysis are discrimination and classification. In discrimination, the goal is to describe graphically (visualization) different features of several known groups. In classification, the goal is to allocate unknown observations to one of several known groups. We have developed new visualization procedures based on traditional estimating procedures and also on robust estimating procedures. We have further developed robust classification procedures. We propose several robust classification procedures based on coordinatewise and affine equivariant, rank-based robust estimates. Empirical studies are performed over many different error distributions. These studies result in empirical efficiencies of the robust and traditional procedures. …


Maximum Likelihood Estimation Of Ordered Multinomial Parameters, Nicholas P. Jewell, John D. Kalbfleisch Oct 2001

Maximum Likelihood Estimation Of Ordered Multinomial Parameters, Nicholas P. Jewell, John D. Kalbfleisch

U.C. Berkeley Division of Biostatistics Working Paper Series

The pool-adjacent violator-algorithm (Ayer, et al., 1955) has long been known to give the maximum likelihood estimator of a series of ordered binomial parameters, based on an independent observation from each distribution (see Barlow et al., 1972). This result has immediate application to estimation of a survival distribution based on current survival status at a set of monitoring times. This paper considers an extended problem of maximum likelihood estimation of a series of ‘ordered’ multinomial parameters. By making use of variants of the pool adjacent violator algorithm, we obtain a simple algorithm to compute the maximum likelihood estimator and demonstrate …


Census 2000 Demographic And Housing Profile Reports, Mark Salling, Ellen Cyran, Sharon Bliss Jan 2000

Census 2000 Demographic And Housing Profile Reports, Mark Salling, Ellen Cyran, Sharon Bliss

All Maxine Goodman Levin School of Urban Affairs Publications

No abstract provided.


Nonparametric Estimation Of The Survival Function Based On Censored Data With Additional Observations From The Residual Distribution, Paul Kvam, Harshinder Singh, Ram C. Tiwari Jan 1999

Nonparametric Estimation Of The Survival Function Based On Censored Data With Additional Observations From The Residual Distribution, Paul Kvam, Harshinder Singh, Ram C. Tiwari

Department of Math & Statistics Faculty Publications

We derive the nonparametric maximum likelihood estimator (NPMLE) of the distribution of the test items using a random, right-censored sample combined with an additional right-censored, residual-lifetime sample in which only lifetimes past a known, fixed time are collected. This framework is suited for samples for which individual test data are combined with left-truncated and randomly censored data from an operating environment. The NPMLE of the survival function using the combined sample is identical to the Kaplan-Meier product-limit estimator only up to the time at which the test items corresponding to the residual sample were known to survive. The limiting distribution …


An Administrative View Of Model Uncertainty In Public Health, Clark D. Carrington Jun 1997

An Administrative View Of Model Uncertainty In Public Health, Clark D. Carrington

RISK: Health, Safety & Environment (1990-2002)

Dr. Carrington reviews several ways to deal with model uncertainty, including those failing to acknowledge any use of models. He then evaluates six such methods with regard to, e.g., transparency and cost of execution.


The Ohio Gis Network: Stage 2 1996 Investment Fund Grant First Year Progress Report To The Ohio Board Of Regents (Ohio Gis Network), Mark Salling Jan 1997

The Ohio Gis Network: Stage 2 1996 Investment Fund Grant First Year Progress Report To The Ohio Board Of Regents (Ohio Gis Network), Mark Salling

All Maxine Goodman Levin School of Urban Affairs Publications

The Ohio Geographic Information Systems Network (Ohio GIS-Net) is an innovative consortium of Ohio’s urban and rural universities. The consortium is building a center of excellence where state-of-the-art geographic information systems (GIS) technology is applied to a research agenda that is critical to Ohio's economic development and central to research issues in policy sciences, civil engineering, public administration, economics and the environmental, urban and regional sciences. This cutting edge technology is an essential component of the basic research infrastructure of universities. It is also a critical resource in state and local economic development efforts, building and maintaining public infrastructure, and …


The Ohio Gis Network: Stage 1 1993 Investment Fund Development Grant Progress Report To The Ohio Board Of Regents (Ohio Gis Network), Mark Salling Jan 1997

The Ohio Gis Network: Stage 1 1993 Investment Fund Development Grant Progress Report To The Ohio Board Of Regents (Ohio Gis Network), Mark Salling

All Maxine Goodman Levin School of Urban Affairs Publications

The Ohio Geographic Information Systems Network (Ohio GIS-Net) is an innovative consortium of Ohio’s urban and rural universities. The consortium is building a center of excellence where state-of-the-art geographic information systems (GIS) technology is applied to a research agenda that is critical to Ohio's economic development and central to research issues in policy sciences, civil engineering, public administration, economics and the environmental, urban and regional sciences. This cutting edge technology is an essential component of the basic research infrastructure of universities. It is also a critical resource in state and local economic development efforts, building and maintaining public infrastructure, and …


Long-Term Posttreatment Upper Incisor Inclination : Relative To Facial Axis Angulation As A Measure For Incisor Placement, David Lawrence Sparks Jun 1994

Long-Term Posttreatment Upper Incisor Inclination : Relative To Facial Axis Angulation As A Measure For Incisor Placement, David Lawrence Sparks

Loma Linda University Electronic Theses, Dissertations & Projects

This study was designed to determine whether upper central incisor inclination approximated the facial axis, long-term, posttreatment, regardless of the initial malocclusion or immediate posttreatment incisor inclination. Lateral head films at pretreatment, immediate posttreatment and long-term posttreatment were traced and evaluated. The sample was divided into facial type. Angle classification and treatment type (extraction vs. non-extraction). Statistical analyses included means, standard deviations, confidence intervals, population t tests and chi-square tabulations.

The results revealed that the upper central incisor did not approximate the facial axis after a minimum of 7 years posttreatment. This failed to support the use of the facial …


Datascan - April 30, 1991, Nova University Apr 1991

Datascan - April 30, 1991, Nova University

DataScan

No abstract provided.


Datascan - March 11, 1991, Nova University Mar 1991

Datascan - March 11, 1991, Nova University

DataScan

No abstract provided.


Datascan - February 18, 1991, Nova University Feb 1991

Datascan - February 18, 1991, Nova University

DataScan

No abstract provided.


Datascan - December 9, 1990, Nova University Dec 1990

Datascan - December 9, 1990, Nova University

DataScan

No abstract provided.


Datascan - November 2, 1990, Nova University Nov 1990

Datascan - November 2, 1990, Nova University

DataScan

No abstract provided.


Datascan - October 19, 1990, Nova University Oct 1990

Datascan - October 19, 1990, Nova University

DataScan

No abstract provided.


Statistical Section (September 1986), Central Bank Of Nigeria Cbn Sep 1986

Statistical Section (September 1986), Central Bank Of Nigeria Cbn

Economic and Financial Review

This is a statistical representation of economic activities in Nigeria in September 1986


Measuring Managerial Efficiency By Data Development Analysis, Jati K Sengupta Jul 1986

Measuring Managerial Efficiency By Data Development Analysis, Jati K Sengupta

IIMB Management Review

No abstract provided.


Statistical Section (September 1984), Central Bank Of Nigeria Cbn Sep 1984

Statistical Section (September 1984), Central Bank Of Nigeria Cbn

Economic and Financial Review

This is the statistical presentations of the developments in the Nigerian economy during the period under review.


Statistical Section (June 1984), Central Bank Of Nigeria Cbn Jun 1984

Statistical Section (June 1984), Central Bank Of Nigeria Cbn

Economic and Financial Review

Statistical tables on central banking, commercial banking, merchant banking, international liquidity, international trade, the flow of funds, money supply, national savings, production, consumer prices, public debt and public finance.


Group Comparability: A Multiattribute Utility Measurement Approach To The Use Of Random Assignment With Small Numbers Of Aggregated Units, C. Anderson Johnson, John W. Graham, Brian R. Flay, William B. Hansen, Linda M. Collins Apr 1984

Group Comparability: A Multiattribute Utility Measurement Approach To The Use Of Random Assignment With Small Numbers Of Aggregated Units, C. Anderson Johnson, John W. Graham, Brian R. Flay, William B. Hansen, Linda M. Collins

CGU Faculty Publications and Research

It is not always possible, especially in large-scale evaluation research, to ensure that random assignment will produce groups that are comparable on any number of potentially important factors. Typically, gaining comparability has been achieved only at the expense of random assignment. A method is presented that allows multivariate comparability while making only minimal restrictions on randomization. The procedure is demonstrated in the context of assigning 63 aggregated units (schools) to 28 experimental and control conditions. Good comparability of groups for all primary main effects and interactions was verified for 15 individual variables.


Statistical Section (September 1983), Central Bank Of Nigeria Cbn Sep 1983

Statistical Section (September 1983), Central Bank Of Nigeria Cbn

Economic and Financial Review

The statistical tables comprised of the following: Central Bank of Nigeria statement of assets & liabilities, Central Bank monthly rediscounts gross, Commercial Banks' statement of assets and liabilities, Analysis of Commercial Banks' loans and advances, Selected predominant interest rates, Ratio of loans and advances to deposits, Net external assets of Commercial Banks, and Liquidity ratios of Commercial and merchants Banks'.


The Maine Coast, A Statistical Source, Maine Coastal Program Sep 1978

The Maine Coast, A Statistical Source, Maine Coastal Program

Maine Collection

The Maine Coast, A Statistical Source

Maine Coastal Program, Natural Resource Planning Division, Maine State Planning Office , Augusta, Maine

First Printing June 1978 - Second Printing September 1978

Contents: Preface / Introduction / Chapter 1 - Demography / Chapter 2 - Land Use and Taxation / Chapter 3 - Economy / Chapter 4 - Housing / Chapter 5 - Transportation / Chapter 6 - Education / Chapter 7 - Recreation / Chapter 8 - Social Services / Chapter 9 - Natural Resources / References / Index


Obesity And Vegetarianism In Seventh-Day Adventist Women, Charlotte Ann Van Camp Darnell Aug 1975

Obesity And Vegetarianism In Seventh-Day Adventist Women, Charlotte Ann Van Camp Darnell

Loma Linda University Electronic Theses, Dissertations & Projects

This thesis describes a comparative study of 82 vegetarian and 21 non-vegetarian Seventh-day Adventist females ages 25 to 65 to discover if there is a possible correlation between diet and weight. The subjects were chosen by random sampling in the specified target population and were personally interviewed by the use of a questionnaire.

The general linear hypothesis analysis shewed that present age and relative weight at age 25 were significant in terms of present relative weight; however, physical activity and socioeconomic stratum were not significant. Diet, defined as vegetarian or non-vegetarian, was only marginally significant.

Conclusions of this study are …