[R] help for compare regression coefficients across groups

Dear all I have data related to cell count across time in 2 different types of cells. I have transformed the count data using a log and I want to test the H0: B cell_ttype1=Bcell_type2 across time for that I am fitting the following model fit_all<-lm(data$count~data$cell_type+data$time+data$cel

[R] problems in installing biomart

Dear Forum my machine runs Ubuntu 9.04. I am trying to install Biomart, what I realize is that something is missing and it can't install XML, RCurl but I don't know what more to do, I looked in previous posts but I did not find infoprmation that helped. Thanks Andreia biocLite("biomaRt") Running b