topic Re: Proc ttest Warning in Statistical Procedures

Proc ttest Warning

billfriend — Wed, 18 Oct 2017 16:20:07 GMT

I received this warning when running a paired proc ttest:

WARNING: There are insufficient nonmissing observations to create a density plot.

There are 19 observations in both the pre and post of the variable I am observing.

I thought maybe I just needed to include:

ods graphics off;

ods exclude all;

proc ttest;

...

ods output ttests=outtest;

run;

ods exclude none;

But the output from this addition showed an empty tValue, DF of 0, and empty probt.

Am I getting this error because the sample size is too small? Or am I doing something wrong? Both variables are numeric.

Re: Proc ttest Warning

Reeza — Wed, 18 Oct 2017 17:02:12 GMT

Are you sure your data has 19non missing observations?

Post a PROC MEANS output of the two variables.

And show the code and log with error.

Re: Proc ttest Warning

billfriend — Wed, 18 Oct 2017 18:05:01 GMT

I think I realized my mistake. What I did was output the means from a proc means statement and then used those outputs to see a difference, but that doesn't work since that's just one observation for both variables. Sorry about that. But is there a better way to analyze likert pre vs post data?