Dear all, I'm facing a problem in estimation of glm model with weibull distribution. I run this : eqn0<-formula(fdh~cup1+cup2+cup3+cup4+fin1+vd1+cm2+cm4+milieu+cpro1+cpro2+cpro3a+cpro3b+schef+log(y)) regWeib0<-vglm(eqn0,family=weibull,subset(br, fdh<1)) I have en estimation but there is a message saying that regularity conditions are violated : Message d'avis : In eval(expr, envir, enclos) : ? MLE regularity conditions are violated(shape <= 2) at the final iteration Then I haved try to apply solution provide in help of the package that consisted to use lschape="logoff" and eschape=list(offset=-2) regWeib0<-vglm(eqn0,family=weibull(lshape='logoff',eshape=list(offset=-2)),subset(br, fdh<1)) Erreur dans if ((temp <- sum(wz[, 1:M, drop = FALSE] < wzepsilon))) warning(paste(temp,? : ? l'argument n'est pas interpr?table comme une valeur logique De plus : Message d'avis : In log(theta + offset) : production de NaN Finaly i use the above function to find initial value for shape (a) and scale (b)? weibullPar<-function(x){ ?f<-function(p,mu=mean(x), sig=((length(x)-1)*var(x))/length(x)){ ????? n<-length(x) ????? a<-p[1] ????? b<-p[2] ????? t1<-(mu-b*gamma(1+1/a))^2 ????? t2<-(sig-((b^2)*gamma(1+2/a)-mu^2))^2 ????? rval<-t1+t2 ????? rval ? } ? optim(c(1,1),f)$par } With the founded initial values I have I have the message. But When try great initial value for ishape and iscale I have this regWeib0<-vglm(eqn0,family=weibull(lshape='logoff',lscale='loge',eshape=list(offset=-2),ishape=22,iscale=6),subset(br, fdh<1)) Messages d'avis : 1: In checkwz(wz, M = M, trace = trace, wzeps = control$wzepsilon) : ? 1525 elements replaced by 1.819e-12 2: In checkwz(wz, M = M, trace = trace, wzeps = control$wzepsilon) : ? 1525 elements replaced by 1.819e-12 3: In checkwz(wz, M = M, trace = trace, wzeps = control$wzepsilon) : ? 1525 elements replaced by 1.819e-12 4: In checkwz(wz, M = M, trace = trace, wzeps = control$wzepsilon) : ? 1525 elements replaced by 1.819e-12 5: In checkwz(wz, M = M, trace = trace, wzeps = control$wzepsilon) : ? 1525 elements replaced by 1.819e-12 6: In checkwz(wz, M = M, trace = trace, wzeps = control$wzepsilon) : ? 1525 elements replaced by 1.819e-12 7: In checkwz(wz, M = M, trace = trace, wzeps = control$wzepsilon) : ? 1525 elements replaced by 1.819e-12 8: In checkwz(wz, M = M, trace = trace, wzeps = control$wzepsilon) : ? 1525 elements replaced by 1.819e-12 9: In eval(expr, envir, enclos) : ? MLE regularity conditions are violated(shape <= 2) at the final iteration MLE regularity condition are still violated but a solution is find ! Can some one help me ? Justin BEM BP 1917 Yaound? T?l (237) 76043774?