Dear Colleagues,
The Division of Biostatistics at the Department of Preventive Medicine invites you to attend the following seminar.
Date: Monday, May 4th, 2020
Time: 2 P.M.
ZOOM Virtual Room Connection: https://tennessee.zoom.us/j/99322680124.
Presenter: Dr. Marco Geraci of University of South Carolina.
Title: “Quantile contours and allometric modelling for risk classification of abnormal ratios with an application to asymmetric growth restriction in preterm infants”
Abstract: In this talk, I will present a novel approach to risk classification based on quantile contours and allometric modelling of multivariate anthropometric measurements. I propose the definition of allometric direction tangent to the directional quantile envelope, which divides ratios of measurements into half-spaces. This in turn provides an operational definition of directional quantile that can be used as cutoff for risk assessment. I will apply the proposed approach to a large dataset from the Vermont Oxford Network containing observations of birthweight (BW) and head circumference (HC) for more than 150,000 preterm infants. The analysis suggests that small preterm infants with large HC-to-BW ratio are at increased risk of mortality as compared to appropriate-for-gestational-age as well as proportionately-growth-restricted preterm infants. This study offers not only an approach to risk classification, but also large-sample estimated cutoffs that can be immediately used by practitioners (Geraci M et al, 2019, Statistical Methods in Medical Research, doi:10.1177/0962280219876963).
About the speaker:
Dr. Marco Geraci obtained a Laurea magna cum laude in Economics from the University of Sassari (Italy) in 2000 and a PhD in Applied Statistics from the University of Florence (Italy) in 2005. He carried out scientific research in several institutions, including the Italian National Council of Research, the University of Manchester (UK), University College London (UK) and the University of South Carolina (UofSC), where he currently holds an appointment as Associate Professor of Biostatistics. He is Director of the Statistical and Data Management Core in the UofSC Research Center for Child Well-Being. His research interests are in quantile inference, random-effects models, multivariate statistics, missing data, and statistical computing, with applications in biomedical sciences, particularly child health. Dr. Geraci has published peer-reviewed articles in statistics, cancer epidemiology, perinatal epidemiology, physical activity, gastroenterology, nuclear medicine and higher education. He also authored 4 statistical software packages on CRAN which, to date, have totaled more than 65,000 downloads. In 2010, Dr. Geraci was awarded Chartered Statistician by the Royal Statistical Society (RSS). He is currently Statistical Reviewer for Lancet Child & Adolescent Health (Elsevier), Associate Editor of the Journal of Applied Statistics (Taylor & Francis), Associate Editor of Statistical Methods and Applications (Springer), and Editorial Board member of the magazine Significance (Wiley on behalf of RSS and ASA), and former Statistical Editor for the Journal of Child Health Care (Sage).
We look forward to seeing you all among us.
Chi-Yang Chiu, Ph.D.
Assistant Professor of Biostatistics
Department of Preventive Medicine, UTHSC