Hi everybody,
Sorry,maybe this is not a bioconductor question,but someone in this list may 
know the answer.I want to re-analysis a microarray data set in GEO(
http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE1159) .The data i 
download are Intensities value from MAS5.0 as indicated on NCBI
GEO.Thecorresponding article
(Prognostically useful gene-expression profiles in acute myeloid leukemia,PMID: 
15084694) described the Normalization procedures as follow:
 
   1. All intensity values were scaled to an average value of 150 per 
   GeneChip according to the method of global scaling, or
normalization, provided
   in the Affymetrix Microarray Suite software, version 5.0 (MAS5.0). 
   2. Since their methods reliably identify samples with an average 
   intensity value of 30 or more but do not reliably discriminate values 
   between 0 and 30, these values were set to 30. 
   3. Analysis 

My question,Do i need to do scaling normalization (to 150 per GeneChip) to 
the data i download form NCBI GEO?
Thanks in advance.

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