### sas >> Statistical question -- compare two columns for statistical difference

by **ni14** » Tue, 25 Jan 2005 04:33:00 GMT

Hello,

I have two columns of continuous data, col1 & col2. I would like to test them to see if they are statistically different or the same. (I son't if I should test to see if they are the same or different). Can anyone please tell me how you do this in SAS? Is it the t-test? If yes, what do you look for in SAS output? I think you use t-test only if col1 & col2 are normally distributed (col1 & col2 by represent probabilities, output form logistic--also I have two more vars col3 &col4 and these are just raw scores out of a neural network package and I need to do the same for these as well). Thanks much.

NICK

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### sas >> Statistical question -- compare two columns for statistical difference

by **art297** » Tue, 25 Jan 2005 07:05:44 GMT

Nick,

Bob already gave you good advice but, since you are comparing two columns

of data, I presume that the independence issue can't be ignored. If your

data are suitable for a t-test, I would guess that you want to look

up 'paired t-test' and meet those assumptions.

And, I'd strongly recommend doing at least some brief reading of a

statistic's text, as the first question should be what kind of statistic

can be used to analyze the type of data you have (e.g., choosing between a

parametric vs a non-parametric test) .. along with whether you meet the

test's assumptions.

Art

--------

them to see if they are statistically different or the same. (I son't if I

should test to see if they are the same or different). Can anyone please

tell me how you do this in SAS? Is it the t-test? If yes, what do you look

for in SAS output? I think you use t-test only if col1 & col2 are normally

distributed (col1 & col2 by represent probabilities, output form logistic--

also I have two more vars col3 &col4 and these are just raw scores out of a

neural network package and I need to do the same for these as well). Thanks

much.

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