错误于gamma(link = identity) : 提供的参数名'link'同'x'不匹配

简单代码
> keti<-read.table("C:\\Documents and Settings\\Administrator\\桌面\\keti.txt",header=T)
> zone<-as.factor(keti$zone)
> bonus<-as.factor(keti$bonus)
> make<-as.factor(keti$make)
> kilometres<-as.factor(keti$kilometres)
> payment<-keti$payment
> insured<-keti$insured
> claims<-keti$claims
> out3<-glm(payment/claims~offset(log(insured))+zone+bonus+make+kilometres,family=gamma(link=log))