flexmix (version 2.0-1)

salmonellaTA98: Salmonella reverse mutagenicity assay

Description

Data on Ames Salmonella reverse mutagenicity assay.

Usage

data("salmonellaTA98")

source

Margolin, B.J., Kaplan, N. and Zeiger, E. (1981) Statistical analysis of the Ames Salmonella/microsome test, Proc. Natl. Acad. Sci. USA, 76, 3779--3783.

Details

This data set is taken from package dispmod provided by Luca Scrucca.

References

Breslow, N.E. (1984), Extra-Poisson variation in log-linear models, Applied Statistics, 33, 38--44.

Wang, P., Puterman, M.L., Cockburn, I.M., and Le, N.D. (1996) Mixed Poisson regression models with covariate dependent rates, Biometrics, 52, 381--400.

Examples

data("salmonellaTA98")
salmonMix <- stepFlexmix(y~1,
                         data=salmonellaTA98, 
                         model=FLXMRglmfix(family="poisson", 
                           fixed=~x + log(x + 10)),                        
                         k=2, nrep=5)
salmonMix.pr <- predict(salmonMix, newdata=salmonellaTA98)
plot(y~x, data=salmonellaTA98, 
     pch=as.character(cluster(salmonMix)), 
     ylim=range(c(salmonellaTA98$y, unlist(salmonMix.pr))))
for (i in 1:2) lines(salmonellaTA98$x, salmonMix.pr[[i]], lty=i)