# Beginner: How to get age-adjusted Z scores of a variable?

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ShaneS on 28 Jul 2017
Hi Everyone,
I have a 25 (subjects) x 68 (variables) matrix. I also have a variable called Age (25 x 1). Now, I would like to get the age-adjusted values of the 68 variables. Could someone teach me how to do that please?
Thanks very much!

Swarooph on 28 Jul 2017
Does the zscores function help? Doc here.
ShaneS on 29 Jul 2017
Hi there,
Thanks. What I am trying to do is to get use MATLAB to get the age-adjusted values of the raw data.
Following that, I will like to transform into Z scores against the mean and SDs from another group.

Shruti Shivaramakrishnan on 31 Jul 2017
I think the following explanation should help:
zscore(X,flag,dim)
If flag is 0 (default), then zscore scales X using the sample standard deviation...
If flag is 1, then zscore scales X using the population standard deviation
zscore(X,flag,dim) standardizes X along dimension dim
Also, if you would like to use zscore functionality without the Statistics and Machine Learning Toolbox, the following answers discussion might help: https://www.mathworks.com/matlabcentral/newsreader/view_thread/275744
Also the "bsxfun" function can help you combine the two functionalities with bsxfun(@rdivide, bsxfun(@minus, Data, meanvalue), standard deviation value)
mean can be calculated using the "mean" function and standard deviation using "std"