Hello all! I teach stats and we use SPSS. My introductory students are doing a correlation matrix this week using a dataset I provided. All of the students except for one were able to recreate the expected results. I went about problem solving...
- The one student who was "wrong" shared her output & syntax - the ouput had the wrong values (so she had not made a reporting error) and the syntax was correct (it matched mine, conducting Pearson's, excluding pairwise, etc.).
- I asked her to share her data, thinking it had an error.
- At first, I copied her data & pasted it in (it's just 200 cases & a few variables in this practice test). When I did that, I got her same wrong answer.
- Then I thought, maybe XLS had some junk in it, so let me import it. When I tried to import her data into SPSS it said "(2004) unexplained error is returned from the server". I went back to the XLS file she sent and saved it as an "all file" then changed the extension to .xls to open it in the older version. Then I was able to import it and exclude spaces, etc. I still got the same wrong answer.
- I'm still thinking the error is in the data.
- I ran descriptives and all of them match.
- There are no missing values on either dataset (hers or mine).
- I did a line by line comparison on about 10% of the data and it all matched.
- Then I think maybe it's process - I verified all cases were selected/no filters, exclusion pairwise, Pearson 2 tail, no corrections applied, etc.
- Then I'm out of ideas and go back to the data - so I transformed all of her variables to ensure there weren't spaces or characters. I used "COMPUTE score1_clean = NUMBER(RTRIM(LTRIM(STRING(score1, F8.2))), F8.2). EXECUTE." for syntax. Then re-ran the matrix wtih the _clean variables and it's STILL THE SAME WRONG ANSWER.
I've used this dataset in this class for 3 semesters and this is the first time I've had this issue. Also she's used this dataset for 3 weeks now, so it's odd that this is the first and only time there've been issues; the descriptives, Shapiro Wilk, t test & ANOVA have all been accurate up to this week's lesson.
Has anybody had this experience or have suggestions on other things to try?
NOTE: I tried attaching the original but it says "failed to upload", I also tried attaching the correct and incorrect example output and syntax files but those are unsupported file types. The attachments are the XLS data after I changed the file type (I got her same 'wrong' answer). I've also attached my sample data (most of the variable names are similar but I think I ended up calling exam 3 an entrance exam on the assignment...) (I got my expected right answer, as did every other student in the class).
Update:
She is using our Monarch MOVE virtual environment, accessing the virtual computing environment with her MacBook Air. The SPSS version is 29.0.1.0. I'm using SPSS installed on my Surface Pro computer, same version 29.0.1.0. Others in the course who got the "right" correlations do use MOVE and/or use i-Devices, but I'm not sure about the specific combinations. Although this shouldn't matter, at this point, I'm open to any explanations!
Resolved:
The original data had a re-ordering issue that I didn't notice but the amazing Jon Peck did!