[BioC] compare expression measures

[Sean Davis]

On 1/4/06 2:57 PM, "Mohammad Esad-Djou" <shahrgol at web.de> wrote:

> 
> Hello, 
> 
> I wants to compare expression measures, which was computed with MAS and RMA.
> 
> But I noticed that the expression-values are very different.
> 
> e.g.: Expt1_R1.CEL: Gen: 1007_s_at
> 
> RMA: 8,06941
> 
> MAS: 236,16853028
> 
> 1. How can I interpret this difference?

MAS is not in log2 units.  RMA is in log2 units.

> 2. And which mathematical methods for comparison between preprocessing can I
> use? 

One place to look would be the affycomp package.  However, you might want to
look at the literature a bit before going too far; some of these comparisons
have been done already with tightly controlled experiments.

Hope that was what you were asking....
Sean