[Felix Bittmann]

As the error message says there are some values missing in variable m and hence the reshape does not work. First you should find out why these values are missing (data error, input error?) To proceed anyway, you must delete these values like

drop if missing(m)

But make sure to check what is the underlying cause.

[Tony Josipovic]

As the error message says there are some values missing in variable m and hence the reshape does not work. First you should find out why these values are missing (data error, input error?) To proceed anyway, you must delete these values like

drop if missing(m)

But make sure to check what is the underlying cause.

Ok, thank you.

[Tony Josipovic]

I was wondering if it would make sense to conduct the signrank and signtest. Anyone having some issues about this? Thanks.

[Felix Bittmann]

Well you can do this if you think that the assumptions of the paired t-test do not hold. Another option is to use the permutation tests for paired samples.