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Enhancing The Communication Competency Of Business Undergraduates: A Consumer Socialization Perspective, K. C. Gehrt, M. O'Brien, David Mease Mar 2009

Enhancing The Communication Competency Of Business Undergraduates: A Consumer Socialization Perspective, K. C. Gehrt, M. O'Brien, David Mease

David Mease

Explaining how individuals acquire the necessary skills and knowledge to effectively participate in society is often accomplished through Socialization Theory. We investigate numerous socialization agents and their relationship with the communication competency of university business majors. Communication competency (reading, writing, and verbal) was measured via both a standardized skill test and self report. Exploratory analysis was conducted upon high and low communication competency groups that were identified via cluster analysis. Our findings generally indicate the most important socialization agents are via personal interactions whereas the least important socialization agents are influencing via primarily electronic or media-based methods.


Notes On The Two-Body Problem, Cathy Kessel Jan 2009

Notes On The Two-Body Problem, Cathy Kessel

Cathy Kessel

No abstract provided.


A Program Evaluation Of A Polypharmacy Sub-Population: Medications, Emergency Room Visits, And Hospitalizations, Brian W. Bresnahan, Kent M. Koprowicz, Sanchita Roy Choudhury, Ed Wong Jan 2009

A Program Evaluation Of A Polypharmacy Sub-Population: Medications, Emergency Room Visits, And Hospitalizations, Brian W. Bresnahan, Kent M. Koprowicz, Sanchita Roy Choudhury, Ed Wong

Kent M Koprowicz

No abstract provided.


Multilevel Functional Principal Component Analysis, Chong-Zhi Di, Ciprian M. Crainiceanu, Brian S. Caffo, Naresh M. Punjabi Jan 2009

Multilevel Functional Principal Component Analysis, Chong-Zhi Di, Ciprian M. Crainiceanu, Brian S. Caffo, Naresh M. Punjabi

Chongzhi Di

The Sleep Heart Health Study (SHHS) is a comprehensive landmark study of sleep and its impacts on health outcomes. A primary metric of the SHHS is the in-home polysomnogram, which includes two electroencephalographic (EEG) channels for each subject, at two visits. The volume and importance of this data presents enormous challenges for analysis. To address these challenges, we introduce multilevel functional principal component analysis (MFPCA), a novel statistical methodology designed to extract core intra- and inter-subject geometric components of multilevel functional data. Though motivated by the SHHS, the proposed methodology is generally applicable, with potential relevance to many modern scientific …


Nonparametric Signal Extraction And Measurement Error In The Analysis Of Electroencephalographic Activity During Sleep, Ciprian M. Crainiceanu, Brian S. Caffo, Chong-Zhi Di, Naresh M. Punjabi Jan 2009

Nonparametric Signal Extraction And Measurement Error In The Analysis Of Electroencephalographic Activity During Sleep, Ciprian M. Crainiceanu, Brian S. Caffo, Chong-Zhi Di, Naresh M. Punjabi

Chongzhi Di

We introduce methods for signal and associated variability estimation based on hierarchical nonparametric smoothing with application to the Sleep Heart Health Study (SHHS). SHHS is the largest electroencephalographic (EEG) collection of sleep-related data, which contains, at each visit, two quasi-continuous EEG signals for each subject. The signal features extracted from EEG data are then used in second level analyses to investigate the relation between health, behavioral, or biometric outcomes and sleep. Using subject specific signals estimated with known variability in a second level regression becomes a nonstandard measurement error problem.We propose and implement methods that take into account cross-sectional and …


Docketology, District Courts, And Doctrine, David A. Hoffman, Alan J. Izenman, Jeffrey R. Lidicker Apr 2008

Docketology, District Courts, And Doctrine, David A. Hoffman, Alan J. Izenman, Jeffrey R. Lidicker

David A Hoffman

Empirical legal scholars have traditionally modeled judicial opinion writing by assuming that judges act rationally, seeking to maximize their influence by writing opinions in politically important cases. Support for this hypothesis has reviewed published opinions, finding that civil rights and other “hot” topics are more to be discussed than other issues. This orthodoxy comforts consumers of legal opinions, because it suggests that opinions are largely representative of judicial work. The orthodoxy is substantively and methodologically flawed. This paper starts by assuming that judges are generally risk averse with respect to reversal, and that they provide opinions when they believe that …


Characterizing Pharmacy And Medical Claims For A Private Insurance Polypharmacy Population, Brian W. Bresnahan, Kent M. Koprowicz, Sanchita Roy Choudhury, Louis P. Garrison, Ed Wong Jan 2008

Characterizing Pharmacy And Medical Claims For A Private Insurance Polypharmacy Population, Brian W. Bresnahan, Kent M. Koprowicz, Sanchita Roy Choudhury, Louis P. Garrison, Ed Wong

Kent M Koprowicz

Objectives: To describe and characterize a group of private insurance members taking multiple medications over a one-year period. Methods: Persons were selected for this polypharmacy analysis if they had at least five unique maintenance prescriptions in their pharmacy claims records for the period of January-March 2005, based on a customized list of chronic medications. The full set of pharmacy and medical claims for these members were evaluated for a twelve month period, October 2004 to September 2005. Standard descriptive statistics were calculated to characterize the population. Logistic regression models were used to assess the association of pharmacy claims and “safety …


The Number Of Sick Persons In A Cohort, Paula Diehr Nov 2007

The Number Of Sick Persons In A Cohort, Paula Diehr

Paula Diehr

To see if the number of sick persons in a cohort was approximately constant over time, we calculated the number of sick persons in a “research” cohort of older adults followed for up to 14 years, and also in a synthetic birth cohort. Methods: In the research cohort, we calculated the actual number of persons in each health state over time, using eight different definitions of “sick”. For the birth cohort, we estimated the number of sick persons each year after birth. Results: The number of sick persons in the research cohort was approximately constant for 14 years, for all …


Site Variation In Ems Treatment, Transport And Survival In Relation To Restoration Of Spontaneous Circulation (Rosc) For Adult Out-Of-Hospital Cardiac Arrest: The Resuscitation Outcomes Consortium (Roc) Epistry, Mohamud R. Daya, Kent M. Koprowicz, Dana M. Zive, Julie E. Cummins, Gena K. Sears, Terri A. Schmidt, Shannon W. Stephens, Ian G. Stiell Jan 2007

Site Variation In Ems Treatment, Transport And Survival In Relation To Restoration Of Spontaneous Circulation (Rosc) For Adult Out-Of-Hospital Cardiac Arrest: The Resuscitation Outcomes Consortium (Roc) Epistry, Mohamud R. Daya, Kent M. Koprowicz, Dana M. Zive, Julie E. Cummins, Gena K. Sears, Terri A. Schmidt, Shannon W. Stephens, Ian G. Stiell

Kent M Koprowicz

Introduction: EMS protocols outlining when to attempt and terminate resuscitation for non-traumatic out-of- hospital cardiac arrest (OHCA) vary substantially across North America. The ROC Epistry is a prospective population based cohort study with uniform Utstein-style data definitions from 11 sites in North America. The purpose of this study was to compare site variation in EMS treatment and transport percentages within the ROC Epistry. We also examined the differences in overall survival in relation to the presence of ROSC prior to transport. Methods: Analysis of ROC Epistry data from 7 sites for all patients > 20 years of age with OHCA between …


Alternative Probeset Definitions For Combining Microarray Data Across Studies Using Different Versions Of Affymetrix Oligonucleotide Arrays, Jeffrey S. Morris, Chunlei Wu, Kevin R. Coombes, Keith A. Baggerly, Jing Wang, Li Zhang Dec 2006

Alternative Probeset Definitions For Combining Microarray Data Across Studies Using Different Versions Of Affymetrix Oligonucleotide Arrays, Jeffrey S. Morris, Chunlei Wu, Kevin R. Coombes, Keith A. Baggerly, Jing Wang, Li Zhang

Jeffrey S. Morris

Many published microarray studies have small to moderate sample sizes, and thus have low statistical power to detect significant relationships between gene expression levels and outcomes of interest. By pooling data across multiple studies, however, we can gain power, enabling us to detect new relationships. This type of pooling is complicated by the fact that gene expression measurements from different microarray platforms are not directly comparable. In this chapter, we discuss two methods for combining information across different versions of Affymetrix oligonucleotide arrays. Each involves a new approach for combining probes on the array into probesets. The first approach involves …


An Econometric Method Of Correcting For Unit Nonresponse Bias In Surveys, Martin Ravallion, Anton Korinek, Johan Mistiaen Dec 2006

An Econometric Method Of Correcting For Unit Nonresponse Bias In Surveys, Martin Ravallion, Anton Korinek, Johan Mistiaen

Martin Ravallion

Past approaches to correcting for unit nonresponse in sample surveys by re-weighting the data assume that the problem is ignorable within arbitrary subgroups of the population. Theory and evidence suggest that this assumption is unlikely to hold, and that household characteristics such as income systematically affect survey compliance. We show that this leaves a bias in the re-weighted data and we propose a method of correcting for this bias. The geographic structure of nonresponse rates allows us to identify a micro compliance function, which is then used to re-weight the unit-record data. An example is given for the US Current …


Synchrony Of Change In Depressive Symptoms, Health Status, And Quality Of Life In Persons With Clinical Depression, Paula Diehr Apr 2006

Synchrony Of Change In Depressive Symptoms, Health Status, And Quality Of Life In Persons With Clinical Depression, Paula Diehr

Paula Diehr

BACKGROUND: Little is known about longitudinal associations among measures of depression, mental and physical health, and quality of life (QOL). We followed 982 clinically depressed persons to determine which measures changed and whether the change was synchronous with change in depressive symptoms. METHODS: Data were from the Longitudinal Investigation of Depression Outcomes (LIDO). Depressive symptoms, physical and mental health, and quality of life were measured at baseline, 6 weeks, 3 months, and 9 months. Change in the measures was examined over time and for persons with different levels of change in depressive symptoms. RESULTS: On average, all of the measures …


The "Duty" To Be A Rational Shareholder, David A. Hoffman Feb 2006

The "Duty" To Be A Rational Shareholder, David A. Hoffman

David A Hoffman

How and when do courts determine that corporate disclosures are actionable under the federal securities laws? The applicable standard is materiality: would a (mythical) reasonable investor have considered a given disclosure important. As I establish through empirical and statistical testing of approximately 500 cases analyzing the materiality standard, judicial findings of immateriality are remarkably common, and have been stable over time. Materiality's scope results in the dismissal of a large number of claims, and creates a set of cases in which courts attempt to explain and defend their vision of who is, and is not, a reasonable investor. Thus, materiality …


Pooling Information Across Different Studies And Oligonucleotide Microarray Chip Types To Identify Prognostic Genes For Lung Cancer., Jeffrey S. Morris, Guosheng Yin, Keith A. Baggerly, Chunlei Wu, Li Zhang Dec 2005

Pooling Information Across Different Studies And Oligonucleotide Microarray Chip Types To Identify Prognostic Genes For Lung Cancer., Jeffrey S. Morris, Guosheng Yin, Keith A. Baggerly, Chunlei Wu, Li Zhang

Jeffrey S. Morris

Our goal in this work is to pool information across microarray studies conducted at different institutions using two different versions of Affymetrix chips to identify genes whose expression levels offer information on lung cancer patients’ survival above and beyond the information provided by readily available clinical covariates. We combine information across chip types by identifying “matching probes” present on both chips, and then assembling them into new probesets based on Unigene clusters. This method yields comparable expression level quantifications across chips without sacrificing much precision or significantly altering the relative ordering of the samples. We fit a series of multivariable …


The Relation Of Dietary Patterns To Future Survival, Health, And Cardiovascular Events In Older Adults, Paula Diehr Dec 2003

The Relation Of Dietary Patterns To Future Survival, Health, And Cardiovascular Events In Older Adults, Paula Diehr

Paula Diehr

BACKGROUND: There have been few long-term follow-up studies of older adults who follow different dietary patterns. METHODS: We cluster-analyzed data on dietary fat, fiber, protein, carbohydrate, and calorie consumption from the U.S. Cardiovascular Health Study (mean age=73), and examined the relationship of the dietary clusters to outcomes 10 years later. RESULTS: The five clusters were named "Healthy diet" (relatively high in fiber and carbohydrate and low in fat), "Unhealthy diet" (relatively high in protein and fat, relatively low in carbohydrates and fiber); "High Calorie," "Low Calorie," and "Low 4," which was distinguished by higher alcohol consumption. The clusters were strongly …


Imputation Of Missing Longitudinal Data: A Comparison Of Methods, Paula Diehr, Jean Mundahl Engels Oct 2003

Imputation Of Missing Longitudinal Data: A Comparison Of Methods, Paula Diehr, Jean Mundahl Engels

Paula Diehr

BACKGROUND AND OBJECTIVES: Missing information is inevitable in longitudinal studies, and can result in biased estimates and a loss of power. One approach to this problem is to impute the missing data to yield a more complete data set. Our goal was to compare the performance of 14 methods of imputing missing data on depression, weight, cognitive functioning, and self-rated health in a longitudinal cohort of older adults. METHODS: We identified situations where a person had a known value following one or more missing values, and treated the known value as a "missing value." This "missing value" was imputed using …


Nullificatory Juries, David A. Hoffman, Kaimipono D. Wenger Oct 2003

Nullificatory Juries, David A. Hoffman, Kaimipono D. Wenger

David A Hoffman

In this Article, we argue that current debates on the legitimacy of punitive damages would benefit from a comparison with jury nullification in criminal trials. We discuss critiques of punitive damages and of jury nullification, noting the surprising similarities in the arguments scholars use to attack these (superficially) distinct outcomes of the jury guarantee. Not only are the criticisms alike, the institutions of punitive damages and jury nullification also turn out to have many similarities: both are, we suggest, examples of what we call "nullificatory juries." We discuss the features of such juries, and consider recent behavioral data relating to …


The Press For Help Project Concept, Program And Working Paper Of Emmanuel Mario B Santos And His Marc Guerrero Communications Inc., Emmanuel Mario B. Santos Aka Marc Guerrero Jan 2003

The Press For Help Project Concept, Program And Working Paper Of Emmanuel Mario B Santos And His Marc Guerrero Communications Inc., Emmanuel Mario B. Santos Aka Marc Guerrero

Emmanuel Mario B Santos aka Marc Guerrero

FORETHOUGHT. DECLARATION OF IDEAOLOGY AND PRINCIPLES. VISION. MISSION. VALUES. GOALS. BASIC HELP project. EDUCATIONAL HELP project. MEDICAL HELP project. LEGAL HELP project. EMERGENCY HELP project. LIVELIHOOD HELP project. SPIRITUAL and CULTURAL HELP project. ENVIRONMENTAL HELP project. REENGINEERING HELP project. INTERNATIONAL HELP project. QUADRO CREDO Matthew 5.1-12, the Jerusalem Bible. The Universal Filipino Beatitudes. SALIN SA FILIPINO. DESIDERATA. AFTERTHOUGHT.


The Aging And Dying Processes And The Health Of Older Adults, Paula Diehr Mar 2002

The Aging And Dying Processes And The Health Of Older Adults, Paula Diehr

Paula Diehr

It is difficult to distinguish changes in health due to aging from those related to dying, because the two processes are highly related. Some potentially treatable conditions may mistakenly be dismissed as due to old age. The goal of this article was to examine the relationships of aging and of dying to changes in 10 health-related variables: self-rated health, depression, ADLs, IADLs, minimental state examination, body mass index, blocks walked per week, bed days, hospitalization, and walking speed (all coded so that higher values were better). We used longitudinal data from the Cardiovascular Health Study to estimate the changes in …


The Importance Of The Normality Assumption In Large Public Health Data Sets, Paula Diehr, Thomas Lumley Jan 2002

The Importance Of The Normality Assumption In Large Public Health Data Sets, Paula Diehr, Thomas Lumley

Paula Diehr

It is widely but incorrectly believed that the t-test and linear regression are valid only for Normally distributed outcomes. The t-test and linear regression compare the mean of an outcome variable for different subjects. While these are valid even in very small samples if the outcome variable is Normally distributed, their major usefulness comes from the fact that in large samples they are valid for any distribution. We demonstrate this validity by simulation in extremely non-Normal data. We discuss situations in which in other methods such as the Wilcoxon rank sum test and ordinal logistic regression (proportional odds model) have …


Weight-Modification Trials In Older Adults: What Should The Outcome Measure Be?, Paula Diehr Jan 2002

Weight-Modification Trials In Older Adults: What Should The Outcome Measure Be?, Paula Diehr

Paula Diehr

BACKGROUND: Overweight older adults are often counseled to lose weight, even though there is little evidence of excess mortality in that age group. Overweight and underweight may be more associated with health status than with mortality, but few clinical trials of any kind have been based on maximizing years of healthy life (YHL), as opposed to years of life (YOL). OBJECTIVE: This paper examines the relationship of body mass index (BMI) to both YHL and YOL. Results were used to determine whether clinical trials of weight-modification based on improving YHL would be more powerful than studies based on survival. DESIGN: …


Patterns Of Self-Rated Health In Older Adults Before And After Sentinel Events, Paula Diehr Jan 2001

Patterns Of Self-Rated Health In Older Adults Before And After Sentinel Events, Paula Diehr

Paula Diehr

OBJECTIVES: To describe and compare patterns of change in self-rated health for older adults before death and before and after stroke, myocardial infarction, congestive heart failure, cardiac procedure, hospital admission for cancer, and hip fracture. DESIGN: "Event cohort," measuring time in months before and after the event. SETTING: Four U.S. communities. PARTICIPANTS: 5888 participants in the Cardiovascular Health Study (CHS), sampled from Medicare rolls and followed up to 8 years. Mean age at baseline was 73. MEASUREMENTS: Self-rated health, including a category for death, assessed at 6-month intervals, and ascertainment of events. METHODS: We examined the percentage that was healthy …


Survival Versus Years Of Healthy Life; Which Is More Powerful As A Study Outcome?, Paula Diehr Jun 1999

Survival Versus Years Of Healthy Life; Which Is More Powerful As A Study Outcome?, Paula Diehr

Paula Diehr

Studies of interventions that are intended to improve patients' health are often evaluated with survival as the primary outcome, even when a measure adjusted for quality of survival, such as years of healthy life (YHL), would seem more appropriate. The purpose of this article is to determine whether studies based on survival are more or less powerful than studies based on YHL in clinical trials where either measure might be appropriate. We used data from the Cardiovascular Health Study (CHS) to estimate the sample size that would be needed in studies of 156 different health conditions, for the two outcome …


Predicting Future Years Of Healthy Life For Older Adults, Paula Diehr Apr 1998

Predicting Future Years Of Healthy Life For Older Adults, Paula Diehr

Paula Diehr

Cost-effectiveness studies often need to compare the cost of a program to the lifetime benefits of the program, but estimates of lifetime benefits are not routinely available, especially for older adults. We used data from two large longitudinal studies of older adults (ages 65-100) to estimate transition probabilities from one health state to another, and used those probabilities to estimate the mean additional years of healthy life that an older adult of specified age, sex, and health status would experience. We found, for example, that 65-year-old women in excellent health can expect 16.8 years of healthy life in the future, …


Optimal Survey Design For Community Intervention Evaluations: Cohort Or Cross-Sectional?, Paula Diehr Dec 1995

Optimal Survey Design For Community Intervention Evaluations: Cohort Or Cross-Sectional?, Paula Diehr

Paula Diehr

Community intervention evaluations that measure changes over time may conduct repeated cross-sectional surveys, follow a cohort of residents over time, or (often) use both designs. Each survey design has implications for precision and cost. To explore these issues, we assume that two waves of surveys are conducted, and that the goal is to estimate change in behavior for people who reside in the community at both times. Cohort designs are shown to provide more accurate estimates (in the sense of lower mean squared error) than cross-sectional estimates if (1) there is strong correlation over time in an individual's behavior at …


Seizure Threshold In Electroconvulsive Therapy: I. Initial Seizure Threshold, C. Edward Coffey, Joseph Lucke, Richard D. Weiner, Andrew D. Krystal, Michael Aque Jan 1995

Seizure Threshold In Electroconvulsive Therapy: I. Initial Seizure Threshold, C. Edward Coffey, Joseph Lucke, Richard D. Weiner, Andrew D. Krystal, Michael Aque

Joseph Lucke

We measured initial seizure threshold by means of a structured stimulus dosage titration procedure in a clinical sample of 111 depressed patients undergoing brief-pulse, constantcurrent electroconvulsive therapy (ECT). Initial seizure threshold was approximately 60 millicoumbs (mc) (10 Joules) on average, but varied widely (6-fold) across patients. Initial seizure threshold was predicted by four variables: electrode placement (higher with bilateral), gender (higher in men), age (higher with increasing age), and dynamic impedance (inverse relationship). Use of neuroleptic medication was associated with a lower seizure threshold. EEG seizure duration was inversely related to initial seizure threshold, but no other relations with seizure …


Seizure Threshold In Electroconvulsive Therapy (Ect): Ii. The Anticonvulsant Effect Of Ect, C. Edward Coffey, Joseph Lucke, Richard D. Weiner, Andrew D. Krystal, Michael Aque Jan 1995

Seizure Threshold In Electroconvulsive Therapy (Ect): Ii. The Anticonvulsant Effect Of Ect, C. Edward Coffey, Joseph Lucke, Richard D. Weiner, Andrew D. Krystal, Michael Aque

Joseph Lucke

To measure the anticonvulsant effects of a course of electroconvulsive therapy (ECT), we used a flexible stimulus dosage titration procedure to estimate seizure threshold at the first and sixth ECT treatments in 62 patients with depression who were undergoing a course of brief pulse, constant current ECT given at moderately suprathreshold stimulus intensity. Seizure threshold increased by approximately 47% on average, but only 35 (56%) of the 62 patients showed a rise in seizure threshold. The rise in seizure threshold was associated with increasing age, but not with gender, stimulus electrode placement, or initial seizure threshold. Dynamic impedance decreased by …