Hi, I'm having problems with rma function, both from the developer package and the standard release. I have included the error below. All I did was ReadAffy on some cel files, and then I tried the rma function. > dataA AffyBatch object size of arrays=712x712 features (71294 kb) cdf=HG-U133A (22283 affyids) number of samples=18 number of genes=22283 annotation=hgu133a notes= > estA<-rma(dataA) Error in density(x, kernel = "epanechnikov", n = 2^14) : x contains missing values Thanks, Kristina