data.frame with 40 rows and 4 variables.
herd two treatment 0 and 1
drug unit of observation or observation ID
dose is continuous \& may be assumed Gaussian
PCVDif is the number of "successes"(N and F specify a binomial response)
Muhammad Yaseen (firstname.lastname@example.org)
Duchateau, L. and Janssen, P. and Rowlands, G. J. (1998).Linear Mixed Models. An Introduction with applications in Veterinary Research. International Livestock Research Institute.