BRIAN BARGER, Ph.D.
Brian Barger is the Quantitative Lead at the Center for Leadership in Disability housed within the Mark Chaffin Center for Healthy Development, where he conducts research and evaluation on multiple disability related projects. His primary research interests include socio-emotional development and measurement in individuals with autism spectrum conditions (ASC), developmental screening, early signs and identification of autism and developmental disabilities, and mental health screening.
MATT HAYAT, Ph.D.
Matt Hayat is a biostatistician with more than 20 years of experience on a host of health-related research studies in a wide array of health and disease areas. He has collaborated with physicians, nurse scientists, statisticians, epidemiologists, and other healthcare workers and researchers. His collaborative efforts have included substantial involvement in the design, conduct, and analysis of randomized trials, and he teaches the graduate course PH8885 Fundamentals of Clinical Trials. He is currently a Co-Investigator on four federally funded clinical trials.
- Statistics collaboration in the health sciences
- Statistics education of health professionals
- Study design and planning
- Design, conduct, and analysis of clinical trials
- Issues related to the use of statistical inference and interpretation of its findings
- Data analysis, interpretation, and statistical reporting
- Development and application of advanced statistical methods for analyzing complex or correlated health data
ALEXANDER KIRPICH, Ph.D.
Alexander Kirpich is a biostatistician with expertise in infectious disease statistical modeling (cholera, dengue, HIV, and others) and bioinformatics. Alexander worked on transmission models of cholera and HIV in collaboration with medical doctors and epidemiologists. Alexander also has expertise in spatial analysis of surveillance cancer data and in work with metabolomics data. His collaboration efforts also include statistical data analyses and relevant assistance for multiple epidemiologists, medical doctors and field scientists. Alexander has broader interests and goals in application of statistical methods to public health and biomedical research questions and policies and to address statistical challenges, such as missing data, asymptomatic infections, underreporting, and noise during data acquisition.
- Infectious disease and biomedical data modeling
- Transmission models
- Analysis of surveillance data, statistical reporting
- Spatial statistics
- Statistics collaboration in various health sciences
RUIYAN LUO, Ph.D.
Ruiyan Luo is a statistician with collaborative experience spanning a wide range of topics in the fields of public health, biology, nutrition, and kinesiology and health. She uses modern statistical methods and develops novel statistical methods to address complex data arising from her collaborations with health scientists. Her methodology research focus is on addressing the difficulties with small sample sizes relative to the number of predictors, as well as situations where explanatory and/or response variables are discrete time observations from curves.
- Bayesian data analysis, hierarchical modeling, and applications
- High dimensional data analysis when the sample size is small and the number of predictors is large: sparse methods for principal component analysis, partial least square, regression and classification
- Longitudinal data analysis, Functional data analysis with functional predictors and/or responses
KATHERINE MASYN, Ph.D.
Katherine Masyn is a biostatistician and prevention science methodologist with over 15 years of experience as a statistician on federally-funded research grants across a wide range of topics in the fields of public health, psychology, and education, utilizing a vast array of modern statistical analysis techniques. She possesses a strong commitment to the effective and accessible dissemination of emerging statistical methodology to substantive researchers and has taught, individually and as part of a team, numerous trainings and workshops, both nationally and internationally. Her own methods research focuses on the use of latent variables to model population heterogeneity in cross-sectional and longitudinal settings.
- Discrete- and continuous-time survival analysis with latent variables
- Latent growth (mixture) models for continuous and categorical outcomes
- Joint models for multiple and multi-faceted longitudinal processes
- Cross-sectional, longitudinal, and multilevel latent class and finite mixture models
- Measurement invariance and differential item functioning in latent class and latent transition analysis
- Factor mixture models: Hybrid latent variable models with latent factors and classes
- Multilevel factor analysis and structural equation modeling
- The intersection of propensity score analysis with latent variable modeling in cross-sectional and longitudinal studies observational studies
- Bayesian structural equation modeling
KATHERINE MASYN, Ph.D.
KAREN NIELSEN, Ph.D.
Karen Nielsen is a statistician with interdisciplinary collaboration experience that spans psychology, communication, kinesiology, gerontology, and health. She has expertise in multilevel modeling and techniques for modeling time-intensive longitudinal data, including data resulting from physiological sensors and wearable technology. Her research interests include developing new statistical techniques for modern data challenges, such as integrating and interpreting multiple data sources with differing timescales, and adapting existing techniques to new use cases.
- Hierarchical / Multi-level modeling
- Analysis of time-intensive longitudinal data
- R programming
- Data visualization
- Study design and planning
- Statistics education
- Development and modification of methods for complex data
YINYING WANG, Ed.D.
Yinying Wang is a social network analysis researcher in the department of educational policy studies in the College of Education and Human Development. Her research interest intersects technology, decision making, neuroscience, and social network analysis in educational leadership and policy. She is also an associate faculty member in the Neuroscience Institute at Georgia State University. In addition to teaching leadership courses, she also teaches Social Network Analysis (EPS 8780). Her background includes medical doctor, classroom teacher, and school administrator.
- Mixed methods social networks research design and applications
- Multiple regression quadratic assignment procedures
- Random graph models of social networks
- Network text analysis
- Discourse network analysis
SCOTT WEAVER, Ph.D.
Scott Weaver is a quantitative methodologist and prevention scientist with over 10 years of experience as a statistician and investigator on projects spanning topics such as normative and atypical developmental trajectories of immigrant and minority youth, health disparities, urban health, HIV, tobacco, community interventions, and substance use/abuse.
- Statistical hypothesis testing and statistical inference
- Generalized Linear Models
- Latent variable models (including structural equation models)
- Multilevel & longitudinal models
- Psychometrics (including classical test theory, factor analysis, latent class analysis, measurement invariance)
- Mediation/moderation analysis
- Finite mixture models for person-centered analysis
- Power analysis
- Methods for missing data
- Survey methods & design
- Quasi-experimental methods and causal inference