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Sas Code Only For Practical Guide To Logistic Regression, Joseph M. Hilbe Jul 2015

Sas Code Only For Practical Guide To Logistic Regression, Joseph M. Hilbe

Joseph M Hilbe

SAS code-only for Practical Guide to Logistic Regression


Wikipedia And Medicine: Quantifying Readership, Editors, And The Significance Of Natural Language, James M. Heilman, Andrew G. West Mar 2015

Wikipedia And Medicine: Quantifying Readership, Editors, And The Significance Of Natural Language, James M. Heilman, Andrew G. West

Andrew G. West

BACKGROUND: Wikipedia is a collaboratively edited encyclopedia. One of the most popular websites on the Internet, it is known to be a frequently used source of healthcare information by both professionals and the lay public.

OBJECTIVE: This document quantifies: (1) The amount of medical content on Wikipedia, (2) the citations supporting Wikipedia’s medical content, (3) the readership of medical content, and (4) the quantity/characteristics of Wikipedia’s medical contributors

METHODS: Using a well-defined categorization infrastructure we identify medically pertinent English Wikipedia articles and links to their foreign language equivalents (Objective 1). With these, Wikipedia’s API can be queried to produce metadata …


Equivalence Of Kernel Machine Regression And Kernel Distance Covariance For Multidimensional Trait Association Studies, Wen-Yu Hua, Debashis Ghosh Jan 2015

Equivalence Of Kernel Machine Regression And Kernel Distance Covariance For Multidimensional Trait Association Studies, Wen-Yu Hua, Debashis Ghosh

Debashis Ghosh

Associating genetic markers with a multidimensional phenotype is an important yet challenging problem. In this work, we establish the equivalence between two popular methods: kernel-machine regression (KMR), and kernel distance covariance (KDC). KMR is a semiparametric regression framework that models covariate effects parametrically and genetic markers non-parametrically, while KDC represents a class of methods that include distance covariance (DC) and Hilbert-Schmidt independence criterion (HSIC), which are nonparametric tests of independence. We show that the equivalence between the score test of KMR and the KDC statistic under certain conditions can lead to a novel generalization of the KDC test that incorporates …


Measuring Privacy Disclosures In Url Query Strings, Andrew G. West, Adam J. Aviv Nov 2014

Measuring Privacy Disclosures In Url Query Strings, Andrew G. West, Adam J. Aviv

Andrew G. West

Publicly posted URLs may contain a wealth of information about the identities and activities of the users who share them. URLs often utilize query strings (i.e., key-value pairs appended to the URL path) as a means to pass session parameters and form data. While often benign and necessary to render the web page, query strings sometimes contain tracking mechanisms, user names, email addresses, and other information that users may not wish to publicly reveal. In isolation this is not particularly problematic, but the growth of Web 2.0 platforms such as social networks and micro-blogging means URLs (often copy-pasted from web …


Fuzzy Mathematical Model For Detection Of Lung Cancer Using A Multi-Nfclass With Confusion Fuzzy Matrix For Accuracy, R.W. W. Hndoosh Sep 2014

Fuzzy Mathematical Model For Detection Of Lung Cancer Using A Multi-Nfclass With Confusion Fuzzy Matrix For Accuracy, R.W. W. Hndoosh

R. W. Hndoosh

and detection of lung cancer data. This model depends on a generic model of a fuzzy perceptron, which can be used to derive a neural fuzzy system for specific domains. The multi neuron-fuzzy classification (Multi-NFClass) model proposed that uses input, hidden layers, output, and subclasses that have a multitude in each class. This model derives fuzzy rules to classify patterns into a number of crisp classes. Firstly, an attempt is made to describe fuzzy if–then rules, and construction of the fuzzy if–then rule, that are determined by the simple steps when its antecedent fuzzy sets are specified by genetic operations, …


Mcd-Description, Joseph M. Hilbe Jul 2014

Mcd-Description, Joseph M. Hilbe

Joseph M Hilbe

Modeling Count Data - description of Data Files with examples using R, Stata and SAS


Mcd Description Data Files: Stata-R-Sas-Excel, Joseph M. Hilbe Jul 2014

Mcd Description Data Files: Stata-R-Sas-Excel, Joseph M. Hilbe

Joseph M Hilbe

Modeling Count Data: Description of Data Files R, Stata, SAS examples


Measuring Gender Difference In Information Sharing Using Network Analysis: The Case Of The Austrian Interlocking Directorship Network In 2009, Carlo Drago, Livia Amidani Aliberti, Davide Carbonai Jul 2014

Measuring Gender Difference In Information Sharing Using Network Analysis: The Case Of The Austrian Interlocking Directorship Network In 2009, Carlo Drago, Livia Amidani Aliberti, Davide Carbonai

Carlo Drago

In recent literature a relevant problem has been the relationship between career/personal contact networks and different career paths. In addition the recent advances in social capital theory have shown the way in which networks impact on personal careers. In particular women’s careers appear to be negatively affected by the informational network structure. The main contribution of this work is to propose empirical evidence of this phenomenon by considering the gendered directorship network with relation to Austria and to show the structural differences by gender in the network. By using community detection techniques we have found various communities in which females …


On The Privacy Concerns Of Url Query Strings, Andrew G. West, Adam J. Aviv May 2014

On The Privacy Concerns Of Url Query Strings, Andrew G. West, Adam J. Aviv

Andrew G. West

URLs often utilize query strings (i.e., key-value pairs appended to the URL path) as a means to pass session parameters and form data. Often times these arguments are not privacy sensitive but are necessary to render the web page. However, query strings may also contain tracking mechanisms, user names, email addresses, and other information that users may not wish to reveal. In isolation such URLs are not particularly problematic, but the growth of Web 2.0 platforms such as social networks and micro-blogging means URLs (often copy-pasted from web browsers) are increasingly being publicly broadcast.

This position paper argues that the …


Bayesian Joint Selection Of Genes And Pathways: Applications In Multiple Myeloma Genomics, Lin Zhang, Jeffrey S. Morris, Jiexin Zhang, Robert Orlowski, Veerabhadran Baladandayuthapani Jan 2014

Bayesian Joint Selection Of Genes And Pathways: Applications In Multiple Myeloma Genomics, Lin Zhang, Jeffrey S. Morris, Jiexin Zhang, Robert Orlowski, Veerabhadran Baladandayuthapani

Jeffrey S. Morris

It is well-established that the development of a disease, especially cancer, is a complex process that results from the joint effects of multiple genes involved in various molecular signaling pathways. In this article, we propose methods to discover genes and molecular pathways significantly associ- ated with clinical outcomes in cancer samples. We exploit the natural hierarchal structure of genes related to a given pathway as a group of interacting genes to conduct selection of both pathways and genes. We posit the problem in a hierarchical structured variable selection (HSVS) framework to analyze the corresponding gene expression data. HSVS methods conduct …


A Hybrid Prognostic Model For Oral Cancer Based On Clinicopathologic And Genomic Markers, Sameem Abdul Kareem Jan 2014

A Hybrid Prognostic Model For Oral Cancer Based On Clinicopathologic And Genomic Markers, Sameem Abdul Kareem

Sameem Abdul Kareem

There are very few prognostic studies that combine both clinicopathologic and genomic data. Most of the studies use only clinicopathologic factors without taking into consideration the tumour biology and molecular information, while some studies use genomic markers or microarray information only without the clinicopathologic parameters. Thus, these studies may not be able to prognoses a patient effectively. Previous studies have shown that prognosis results are more accurate when using both clinicopathologic and genomic data. The objectives of this research were to apply hybrid artificial intelligent techniques in the prognosis of oral cancer based on the correlation of clinicopathologic and genomic …


U.S. Masters Track Participation Reveals A Stable Gender Difference In Competitiveness, Robert O. Deaner, Vittorio Addona, Michael P. Mead Jan 2014

U.S. Masters Track Participation Reveals A Stable Gender Difference In Competitiveness, Robert O. Deaner, Vittorio Addona, Michael P. Mead

Vittorio Addona

No abstract provided.


The Applicability Of Greulich And Pyle Atlas To Assess Skeletal Age For Four Ethnic Groups, Sameem Abdul Kareem Dec 2013

The Applicability Of Greulich And Pyle Atlas To Assess Skeletal Age For Four Ethnic Groups, Sameem Abdul Kareem

Sameem Abdul Kareem

Background: Recently, determination of skeletal age, defined as the assessment of bone age, has rapidly become an important task between forensic experts and radiologists. The GreulichePyle (GP) atlas is one of the most frequently used methods for the assessment of skeletal age around the world. After presentation of the GP approach for the estimation of the bone age, much research has been conducted to examine the usability of this method in various geographic or ethnic categories. This study investigates on a small-scale and compares the reliability of the GP atlas for assessment of the bone age for four ethnic groups …


Enabling And Encouraging Greater Diversity In Ict, Madeleine Rh Roberts, Tanya Mcgill Jan 2013

Enabling And Encouraging Greater Diversity In Ict, Madeleine Rh Roberts, Tanya Mcgill

Madeleine R. H. Roberts

There is now a far greater level of heterogeneity in the university cohort in age, experience and cultural and socio-economic backgrounds than in the past. This means that assumptions about the equality of student knowledge and ability that may still exist could be causing difficulties for female and male students who are not school leavers or native English speakers. The issues faced by mature-age, international, and low socio-economic background female and male students are diverse and the potential strategies to assist in retaining current students and attracting future students are varied. Therefore, the strategies employed must address as many of …


The Predictive Hazard Ratio For Biomarker Evaluation Studies, Debashis Ghosh Jan 2013

The Predictive Hazard Ratio For Biomarker Evaluation Studies, Debashis Ghosh

Debashis Ghosh

There is tremendous scientific and medical interest in the use of biomarkers to better facilitate medical decision making. In this article, we present a simple framework for assessing the predictive ability of a biomarker. The methodology requires use of techniques from a subfield of survival analysis termed semicompeting risks; results are presented to make the article self-contained. A crucial parameter for evaluating is the predictive hazard ratio, which is different from the usual hazard ratio from Cox regression models for right-censored data. This quantity will be defined; its estimation, inference and adjustment for covariates will be discussed. Aspects of censoring …


Using Methods From The Data-Mining And Machine-Learning Literature For Disease Classification And Prediction: A Case Study Examining Classification Of Heart Failure Subtypes, Peter C. Austin Jan 2013

Using Methods From The Data-Mining And Machine-Learning Literature For Disease Classification And Prediction: A Case Study Examining Classification Of Heart Failure Subtypes, Peter C. Austin

Peter Austin

OBJECTIVE: Physicians classify patients into those with or without a specific disease. Furthermore, there is often interest in classifying patients according to disease etiology or subtype. Classification trees are frequently used to classify patients according to the presence or absence of a disease. However, classification trees can suffer from limited accuracy. In the data-mining and machine-learning literature, alternate classification schemes have been developed. These include bootstrap aggregation (bagging), boosting, random forests, and support vector machines.

STUDY DESIGN AND SETTING: We compared the performance of these classification methods with that of conventional classification trees to classify patients with heart failure (HF) …


First Temperature Observations With The Usu Very Large Rayleigh Lidar: An Examination Of Mesopause Temperatures, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Marcus J. Bingham, Lance W. Petersen, Matthew T. Emerick Dec 2012

First Temperature Observations With The Usu Very Large Rayleigh Lidar: An Examination Of Mesopause Temperatures, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Marcus J. Bingham, Lance W. Petersen, Matthew T. Emerick

Leda Sox

No abstract provided.


Statistical Methods For Social Network Analysis With Applications In Economics, Carlo Drago Sep 2012

Statistical Methods For Social Network Analysis With Applications In Economics, Carlo Drago

Carlo Drago

No abstract provided.


Technical Assistance, Knowledge Gatekeeping And Indigenous Knowledge: Re-Thinking The International Development Practice, Deogratias Harorimana Sr Sep 2012

Technical Assistance, Knowledge Gatekeeping And Indigenous Knowledge: Re-Thinking The International Development Practice, Deogratias Harorimana Sr

Dr Deogratias Harorimana

This paper presents results from a multi-disciplinary conceptual analysis of development theory and practice. It reviews issues raised and proposes a shift in the epistemology of possession towards an epistemology of practice which is guided by the following aspects (1) The consideration of the learning culture of parties involved, (2) the ability and willingness for decontextualisation of the knowledge by the source and (3) the ability to embedded it by recipients (embededness ), (4) the importance that is attached to knowledge of the host country as reflected through (5) Similarity in culture, values, understanding of context and knowledge bases; (6) …


Technical Factors Utilised By Elite Archers: Towards Setting An Agenda For Archery, Andrew J. Callaway, Shelley A. Broomfield Jul 2012

Technical Factors Utilised By Elite Archers: Towards Setting An Agenda For Archery, Andrew J. Callaway, Shelley A. Broomfield

Andrew J Callaway

Archery, in one form or another, has been around for thousands of years yet research into what makes an archer 'good' is still in its infancy. There are several variations over bow type and different competitions which can be competed, previous works have focused on Recurve (Olympic) bow types whilst Compound have generally been ignored. Research in the area has tended to focus on muscle activation patterns using Electromyography (EMG) and aiming based studies, where generally scores are used as a factor to correlate to.

AIM: The aim of this research is to offer a development from the use of …


Comparing Years Of Healthy Life, Measured In 16 Ways, For Normal Weight And Overweight Older Adults, Paula Diehr Jun 2012

Comparing Years Of Healthy Life, Measured In 16 Ways, For Normal Weight And Overweight Older Adults, Paula Diehr

Paula Diehr

Introduction. The traditional definitions of overweight and obesity are not age specific, even though the relationship of weight to mortality is different for older adults. Effects of adiposity on aspects of health beside mortality have not been well investigated. Methods. We calculated the number of years of healthy life (YHL) in the 10 years after baseline, for 5,747 older adults. YHL was defined in 16 different ways. We compared Normal and Overweight persons, classified either by bodymass index (BMI) or by waist circumference (WC). Findings. YHL for Normal and Overweight persons differed significantly in 25% of the comparisons, of which …


Privacy Protection Framework With Defined Policies For Service-Oriented Architecture, David Allison, Miriam A M Capretz, Hany Elyamany, Shuying Wang Jan 2012

Privacy Protection Framework With Defined Policies For Service-Oriented Architecture, David Allison, Miriam A M Capretz, Hany Elyamany, Shuying Wang

Miriam A M Capretz

Service-Oriented Architecture (SOA) is a computer systems design concept which aims to achieve reusability and inte-gration in a distributed environment through the use of autonomous, loosely coupled, interoperable abstractions known as services. In order to interoperate, communication between services is very important due to their autonomous nature. This communication provides services with their functional strengths, but also creates the opportunity for the loss of privacy. In this paper, a Privacy Protection Framework for Service-Oriented Architecture (PPFSOA) is described. In this framework, a Privacy Service (PS) is used in combination with privacy policies to create privacy contracts that out-line what can …


Impact Of Crm Systems On Organisational Performance: A Case Study Of Anz Bank, Deogratias Harorimana Sr Jan 2012

Impact Of Crm Systems On Organisational Performance: A Case Study Of Anz Bank, Deogratias Harorimana Sr

Dr Deogratias Harorimana

This paper reports case study results analysis of the ANZ Bank in the Pacific Region. The case study results show that ANZ has a well-established CRM system supporting its marketing and sales activities, but equally the results indicate mixed scenarios. A positive relationship between CRM to performance was established. That is, it has a positive contribution to the bank’s performance, both financial and non-financial. There is also negative feedback on the bank’s CRM system which illustrates that CRM system can also have negative consequences. CRM success is questionable from a stand-alone perspective. Although there are encouraging results from the use …


Automated Web Based System For Bone Age Assessment Using Historam Technique, Ram Gopal Raj Jan 2012

Automated Web Based System For Bone Age Assessment Using Historam Technique, Ram Gopal Raj

Ram Gopal Raj

Bone age assessment (BAA) is often used to evaluate the growth status of children as part of the detection of hormonal problems and genetic disorders. The determination of skeletal maturity is done based on a radiological examination of the hand-wrist skeletal area.This paper introduces a novel approach for BAA that utilizes a histogram based comparison technique. This approach is executed as a web based system that uses an image repository and similarity measures based on content-based image retrieval. This study aims to overcome to the limitations of traditional methods utilized to estimate human age which were often imprecise.The system provides …


A Systematic Mapping Approach Of 16q12.2/Fto And Bmi In More Than 20,000 African Americans Narrows In On The Underlying Functional Variation: Results From The Population Architecture Using Genomics And Epidemiology (Page) Study Jan 2012

A Systematic Mapping Approach Of 16q12.2/Fto And Bmi In More Than 20,000 African Americans Narrows In On The Underlying Functional Variation: Results From The Population Architecture Using Genomics And Epidemiology (Page) Study

Shuo Jiao

Genetic variants in intron 1 of the fat mass– and obesity-associated (FTO) gene have been consistently associated with body mass index (BMI) in Europeans. However, follow-up studies in African Americans (AA) have shown no support for some of the most consistently BMI–associated FTO index single nucleotide polymorphisms (SNPs). This is most likely explained by different race-specific linkage disequilibrium (LD) patterns and lower correlation overall in AA, which provides the opportunity to fine-map this region and narrow in on the functional variant. To comprehensively explore the 16q12.2/FTO locus and to search for second independent signals in the broader region, we fine-mapped …


Genome-Wide Search For Gene-Gene Interactions In Colorectal Cancer Jan 2012

Genome-Wide Search For Gene-Gene Interactions In Colorectal Cancer

Shuo Jiao

Genome-wide association studies (GWAS) have successfully identified a number of single-nucleotide polymorphisms (SNPs) associated with colorectal cancer (CRC) risk. However, these susceptibility loci known today explain only a small fraction of the genetic risk. Gene-gene interaction (GxG) is considered to be one source of the missing heritability. To address this, we performed a genome-wide search for pair-wise GxG associated with CRC risk using 8,380 cases and 10,558 controls in the discovery phase and 2,527 cases and 2,658 controls in the replication phase. We developed a simple, but powerful method for testing interaction, which we term the Average Risk Due to …


Generating Survival Times To Simulate Cox Proportional Hazards Models With Time-Varying Covariates., Peter C. Austin Jan 2012

Generating Survival Times To Simulate Cox Proportional Hazards Models With Time-Varying Covariates., Peter C. Austin

Peter Austin

Simulations and Monte Carlo methods serve an important role in modern statistical research. They allow for an examination of the performance of statistical procedures in settings in which analytic and mathematical derivations may not be feasible. A key element in any statistical simulation is the existence of an appropriate data-generating process: one must be able to simulate data from a specified statistical model. We describe data-generating processes for the Cox proportional hazards model with time-varying covariates when event times follow an exponential, Weibull, or Gompertz distribution. We consider three types of time-varying covariates: first, a dichotomous time-varying covariate that can …


Identifying Unique Neighborhood Characteristics To Guide Health Planning For Stroke And Heart Attack: Fuzzy Cluster And Discriminant Analyses Approaches, Ashley Pedigo, William Seaver, Agricola Odoi Jul 2011

Identifying Unique Neighborhood Characteristics To Guide Health Planning For Stroke And Heart Attack: Fuzzy Cluster And Discriminant Analyses Approaches, Ashley Pedigo, William Seaver, Agricola Odoi

Agricola Odoi

Background: Socioeconomic, demographic, and geographic factors are known determinants of stroke and myocardial infarction (MI) risk. Clustering of these factors in neighborhoods needs to be taken into consideration during planning, prioritization and implementation of health programs intended to reduce disparities. Given the complex and multidimensional nature of these factors, multivariate methods are needed to identify neighborhood clusters of these determinants so as to better understand the unique neighborhood profiles. This information is critical for evidence-based health planning and service provision. Therefore, this study used a robust multivariate approach to classify neighborhoods and identify their socio-demographic characteristics so as to provide …


Gender Participation In The Management Of Tricycle Transport For Youth Empowerment And Sustainable Development In Kano State, Nigeria, Nuratu Muhammed Jun 2011

Gender Participation In The Management Of Tricycle Transport For Youth Empowerment And Sustainable Development In Kano State, Nigeria, Nuratu Muhammed

Confluence Journal Environmental Studies (CJES), Kogi State University, Nigeria

The research examined gender participation in the management of tricycle for youth empowerment and sustainable development in Kano state, Nigeria. Stratified random sampling technique was used to select samples of drivers(150), passengers (150) and owners/managers the female tricycle owners fell under this category and they numbered(65).All together a total of 365 samples were selected for the study. Data obtained from the primary data was analyzed using simple statistical techniques and chi square test to ascertain whether there was any significant differences in some of the variables tested. The results of the analysis revealed that the main difference was found in …


U.S. Cultural Involvement And Its Association With Co-Occurring Substance Abuse And Sexual Risk Behaviors Among Youth In The Dominican Republic, Elián P. Cabrera-Nguyen, Juan B. Peña Jun 2011

U.S. Cultural Involvement And Its Association With Co-Occurring Substance Abuse And Sexual Risk Behaviors Among Youth In The Dominican Republic, Elián P. Cabrera-Nguyen, Juan B. Peña

Elián P. Cabrera-Nguyen

We examined the relationship of US cultural involvement with substance abuse and sexual risk behavior profiles from our nationally representative sample of public high school students in the Dominican Republic. Using a novel methodological approach to control for selection bias, we examined explanations for the so-called Latino or Hispanic immigrant paradox. A latent class regression analysis with manifest and latent covariates found that US cultural involvement indicators were independent and robust predictors of increased risk of co-ocurring substance abuse and sexual risk behaviors. Implications for prevention efforts targeting risk behaviors among Latino/a adolescents in the US and abroad are considered.