Incorrect calculatons in data analysis

[k4katherine]

Hi everyone! Has anyone previously come across issues with statistical analysis in data analysis? Most of the tests are working fine but for some of the t-tests the t-statistic is calculated incorrectly and sometimes reports a positive t-statistic when it should be a negative number. I'm wondering if there is a setting somewhere that could impact this, or something about the format of the raw data? It's strange because most of the tests are 100% fine... Would appreciate any input or suggestions if there are any experts out there. Cheers.

[davidm]

Katherine,

Attach your worksheet. Have never encountered this problem.


David

[k4katherine]

Hi David,
The attached files are a t-test done on my machine (t-test incorrect) and the same test, same data, from my classmate (t-test correct). I was the only one that got different numbers in the output. Also the t-test mean (done in data analysis plus) that reported a positive t-statistic which should have been negative (the mean is less than the hypothesised mean). That one was easy for me to pick up an error but not so easy to see that something was wrong with the t-test without calculating the whole thing by hand to check!
Thanks