[R] scaling advice

[Data Analytics Corp.]

Hi,

I have a consultants nightmare -- I was given a project that another 
consultant did and I was told to do the same calculations, but there's 
no documentation on what he did.  Basically, I have yes/no answers to 
survey questions about the effectiveness of product attributes by 
brands.  There are 44 attributes and 13 brands.  The other guy scaled 
the proportion of respondents who said Yes to be mean 0 and variance 
1.0, apparently doing this by brand within each attribute.  He then 
created a matrix of 44 rows for the attributes and 13 columns for the 
brands.  No problem with this; I can always replicate this much.  But 
then he apparently rescaled this 44x13 matrix so that the rows all sum 
to zero and the columns all sum to zero.  None of the row and column 
standard deviations are 1.0.  This I can't see how to do.  How can I 
rescale the rows and columns so that they all sum to zero?  Any suggestions?

Thanks,

Walt

________________________

Walter R. Paczkowski, Ph.D.
Data Analytics Corp.
44 Hamilton Lane
Plainsboro, NJ 08536
________________________
(V) 609-936-8999
(F) 609-936-3733
walt at dataanalyticscorp.com
www.dataanalyticscorp.com