# # Look at the Akaike information criteria for the colon data # ctheta <- 1:20/2 cdf <- cpl <- cpen <- ctheta initials <- rep(0, 4+ length(unique(colon$id))) for (i in seq(along=ctheta)) { tfit <- coxph(Surv(time, status) ~ rx + extent + node4 + + frailty(id, theta=ctheta[i]) + strata(etype), colon, init=initials, iter=30) cat(i) assign(paste("tfit", i, sep='.'), tfit) cdf[i] <- sum(tfit$df) cpl[i] <- tfit$plik cpen[i] <- tfit$penalty initials <- c(tfit$coef, tfit$frail) }