University of Waterloo
28 octobre 2016 de 15 h 30 à 17 h 30 (heure de Montréal/HNE) Sur place
Two-phase studies are frequently used when observations on certain variables are expensive or difficult to obtain. One such situation is when a cohort exists for which certain variables have been measured (phase 1 data); then, a subsample of individuals is selected, and additional data are collected on them (phase 2). Efficiency for tests and estimators can be increased by basing the selection of phase 2 individuals on data collected at phase 1. For example, in large cohorts, expensive genomic measurements are often collected at phase 2, with oversampling of persons with “extreme” phenotypic responses. A second example is casecohort or nested casecontrol studies involving times to rare events, where phase 2 oversamples persons who have experienced the event by a certain time. In this talk I will describe twophase studies on failure times, present efficient methods for testing covariate effects. Some extensions to more complex outcomes and areas needing further development will be discussed.
AdresseRoom 1205, Burnside Hall, 805 Sherbrooke West