數學系演講公告 主講 人: 陳珍信 教授 中央研究院統計科學研究所 台灣大學公共衛生學院流行病學與預防醫學研究所 講 題:Location-Scale Regression Models with Non-Susceptibility in Event History Analysis 日 期:99年11月09日(星期二) 時 間:下午3:30-4:20 地 點:數學系(科學館S433室) Abstract In population-based studies and genomic medicine research, it is important to delineate genetic, environmental effects and their interactions on specific complex diseases/disorders. Statistical methods for analyzing this kind of data have been developing. In most of the cases, outcomes of the disease/disorder under study are treated as either a dichotomous status or a continuous measurement of age at onset. The former approaches do not consider the probability of later onset for observed non-cases, while the latter approaches ignore the disease non-susceptibility in the non-cases, who did not inherit the related genes or were never exposed to deleterious environmental factors. These two kinds of approaches may render misleading interpretations. In this presentation we briefly review the conventional survival analysis which implicitly assumes all the study subjects are susceptible to the event. To analyze the non-susceptibility, recent studies proposed mixture regression models to investigate the respective risk factors for the probability of disease susceptibility and the age-at-onset distribution simultaneously for right censored data. In epidemiological studies with longitudinal data, we often encounter left, interval and right censored data, as well as possible left truncated data due to different entry ages of recruited healthy subjects. The resultant survival curves may emerge plateaus on right tails and multiple crossings over covariate strata. To tackle these issues of incomplete data, we present the mixture regression model combining the logistic model with the accelerated failure time location-scale model. We also apply the model to analyze age-at-onset studies in a few epidemiological research projects in Taiwan. A three-component mixture regression model is extended to study the willingness-to-pay for non-market health services using double-bound dichotomous choice contingent valuation surveys. 歡 迎 參 加 敬 請 張 貼 淡江大學數學系 敬啟