Dear all,I'm a newbie to Survival Analysis and I have some questions about the functions in the survival package.First, what's the difference between survreg and coxph? Say fit1<- survreg(survObj ~ var1 + var2 + var3, dist= 'whatever') and fit2<- coxph(survObj ~ var1 + var2 + var3), what's the difference between fit1 and fit2? They all do regression on explanatory variables. What does it mean dist in survreg?Second, what's the difference in these two specifications of the proportional hazard model?coxph(survObj ~ var1 + strata(var2))coxph(survObj ~ var1*strata(var2))Thanx,Pierre _________________________________________________________________ [[elided Hotmail spam]] [[alternative HTML version deleted]]