What methylation values are usually supplied within ncbi geo 450k series matrices?
I am going to automatically download a lot of GSE (~80) matrices and to use them in my analysis. Before this I want to double check here if I understand correctly what data is within those matrices.
I know that they contain sample, contact information, etc. But what about methylation data? Are those values already normalised, batch corrected? Or does this vary between each study?