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Hello, I wish to?censor 10% of my sample units of 50 from a Weibull distribution. Below is the code for it. I will need to know whether what i have done is correct and if not, can i have any suggestion to improve it? Thank you ?p=2;b=120 n=50 r=45 t<-rweibull(r,shape=p,scale=b) meantrue<-gamma(1+(1/p))*b meantrue cen<- runif(n-r,min=0,max=meantrue) cen Chris Guure Researcher, Institute for Mathematical Research UPM

...ch states that Error in optim(start, fn = z, data = q, hessian = T) :? ? objective function in optim evaluates to length 25 not 1 can somebody?help me remove this error. Is my censoring approach correct. n=25;rr=1000 p=1.5;b=1.2 for (i in 1:rr){ q<-c(t,cen) t<-rweibull(25,shape=p,scale=b) meantrue<-gamma(1+(1/p))*b meantrue d<-meantrue/0.30 cen<- runif(25,min=0,max=d) cen s<-ifelse(t<=cen,1,0) z<-function(data,p){? beta<-p[1] eta<-p[2] log1<-(n*cen*log(p[1])-n*cen*(p[1])*log(p[2])+cen*(p[1]-1)*sum(log(t))-n*sum((t/(p[2]))^(p[1]))) return(-log1) } start <-c(0.5,...

...he code is given below; The problem is that, the newton-Raphson approach isnt working and i do not know what is wrong.?Can somebody suggest something or help in identifying what the problem might be.? p1<-0.6;b<-2 n=20;rr=5000 U<-runif(n,0,1) for (i in 1:rr){ x<-(-log(1-U^(1/p1))/b) ?meantrue<-gamma(1+(1/p1))*b ? meantrue ? d<-meantrue/0.30 ? cen<- runif(n,min=0,max=d) ? s<-ifelse(x<=cen,1,0) ? q<-c(x,cen) ? ? z<-function(data, p){? ? ? shape<-p[1] ? ? scale<-p[2] ? ? log1<-n*sum(s)*log(p[1])+ n*sum(s)*log(p[2])+(p[1]-1)*sum(s)*log(1-((exp(-(p[2])*sum(x)))...

...ion to obtain the desire estimate is where i have a problem with, > ?can some body help? > ?My likelihood equation is for a random type-I censoring where time for the censored units is different for each unit. > ? > n=50;r=35 > p=0.8;b=1.5 > t<-rweibull(50,shape=p,scale=b) > meantrue<-gamma(1+(1/p))*b > meantrue > d<-meantrue/0.30 > > cen<- runif(50,min=0,max=d) > cen > s<-ifelse(t<=cen,1,0) > s > > z<-function(p){? > shape<-p[1] > scale<-p[2] > log1<-(r*log(p[1])-r*(p[1])*log(p[2])+(p[1]-1)*sum(log(t))-sum((t/(p[...