Session 8 Homework Q&A

Update: Received this email over the weekend.

Dear sir

Actually, I think the issue is not with column V7 (V7 has both 1's and 0's), but rather with column V19, which is all "." (dots) when added to SPSS.
On eliminating V19 and adding V7 back in, the factor reduction is running smooth.
R

Update: Have just sent in my solution to session 7 homeworks to teh AAs. Should be up on LMS soon.

Hi all,

Well, well.. an early bird decided to take on Session 8 HW aaj hi....

Here's an email I got from V:

Dear Prof.,


When trying to do the “factor analysis” on the “hw1 ice-cream dataset” I am encountering the following issue –

The data type is “nominal” (0,1) and when I run a factor analysis on SPSS, it throws up the following error message –

Warnings

There are fewer than two cases, at least one of the variables has zero variance, there is only one variable in the analysis, or correlation coefficients could not be computed for all pairs of variables. No further statistics will be computed.

Could you please help with what I might be doing wrong.

Thanks!

Regards,
V

My response:

Aha.


Check up the descriptive stats. See if all the variables are indeed 'variables'. If I recall correctly, one of the questions was such that *everybody* answered the same way.

So the std deviation in that column was zero. Will need to eliminate that one first.

Sudhir

And then his response:

Thanks professor!


It seems to be working after I eliminated V7.

Regards,
V

All's well that ends well I guess.

Sudhir