[R-sig-eco] Fitting a Weibull with a 0 dose

Katie, I second Ben's suggestion to use functions in the drc library, not nls(). Not only do those functions model binomial or overdispersed binomial data, but they provide estimates and confidence intervals for the EC50 and any other EC, e.g. EC10. However, neither handles x=0 very well.

Re: [R-sig-eco] Fitting a Weibull with a 0 dose

Dixon, Philip M [STAT] pdixon@... writes: Katie, I second Ben's suggestion to use functions in the drc library, not nls(). Not only do those functions model binomial or overdispersed binomial data, but they provide estimates and confidence intervals for the EC50 and any other EC, e.g. EC10.