search for: epil2

Dear r-helpers, Spencer Graves and Manual Morales proposed the following methods to simulate p-values in lme4: ************preliminary************ require(lme4) require(MASS) summary(glm(y ~ lbase*trt + lage + V4, family = poisson, data = epil), cor = FALSE) epil2 <- epil[epil$period == 1, ] epil2["period"] <- rep(0, 59); epil2["y"] <- epil2["base"] epil["time"] <- 1; epil2["time"] <- 4 epil2 <- rbind(epil, epil2) epil2$pred <- unclass(epil2$trt) * (epil2$period > 0) epil2$subject <...

...anova(result.b,result.f)$Chisq[[2]] } val <- sum(unlist(lapply(chi.stat, function(x) if(x>stat) 1 else 0)))/iter hist(chi.stat) return(val) } p.value(10,test.stat) # Increase to >=1000 to get a reasonable P-value! # Script to generate data, from section 10.4 of MASS epil2 <- epil[epil$period == 1, ] epil2["period"] <- rep(0, 59); epil2["y"] <- epil2["base"] epil["time"] <- 1; epil2["time"] <- 4 epil2 <- rbind(epil, epil2) epil2$pred <- unclass(epil2$trt) * (epil2$period > 0) epil2$subject <...

library(glmmADMB) #Example for glmm.admb data(epil2) glmm.admb(y~Base*trt+Age +Visit,random=~Visit,group="subject",data=epil2,family="nbinom") Gives: Error in glmm.admb(y ~ Base * trt + Age + Visit, random = ~Visit, group = "subject", : The function maximizer failed ****************** R version 2.4.1 RC (2006-12-...

...ry (Windows dll) that can be called from R via the driver function glmm.admb(). The function can be downloaded from http://otter-rsch.com/admbre/examples/nbmm/nbmm.html The two models of Booth et al are fit by the commands: glmm.admb(y~Base*trt+Age+Visit,random=~1,group="subject",data=epil2) glmm.admb(y~Base*trt+Age+Visit,random=~Visit,group="subject",data=epil2) I will be happy to receive feedback on the function glmm.admb(). Best regards, Hans Skaug Reference: Booth J.G.; Casella G.; Friedl H.; Hobert J.P, Negative binomial loglinear mixed models. Statistical Mode...

...on R help list I saw that more experienced people recommended using lmer (from lme4 pack), glmmPQL (from MASS) or glmm.admb (from glmmADMB pack)     My first problem: yesterday this syntax was ok, now I get this weird message (I got it before when I was using my own set of data)   >        data(epil2) >        glmm.admb(y~Base*trt+Age+Visit,random=~Visit,group="subject",data=epil2,family="nbinom") 'C:/Documents' is not recognized as an internal or external command, operable program or batch file. Error in glmm.admb(y ~ Base * trt + Age + Visit, random = ~Visit, gr...

Dear R users, Does anyone know how to get standard errors of the parameter estimates in glmm.admb? Thanks, Istvan

Hi, I have to analyse the number of provisioning trips to nestlings according to a number of biological and environmental factors. I was thinking of building a mixed-effects model with species and nestid as random effects, using a Poisson distribution, but the data are overdispersed (variance/mean = 5). I then thought of using a mixed-effects model with negative binomial distribution, but I have