Data Merging in SPSS: Help much appreciated

[gemma7]

Hello

I need to merge 2 datafiles in SPSS. The variables are ones that I want to compare at 2 different times (time 1 and time 2) but the cases are not matched (i.e. it is not a within subjects design).

Another thing to complicate this is that the variables are not all identical at time 1 and time 2 (although the varaibles I want to compare directly are!) But what this means is that it's not just a case of copying one data file and pasting it to the bottom of the other, because of the variables that don't match up.

Is it worth me just cutting and pasting the variables I want to compare into a new data file and add a variable at the start (to identify time 1 or time 2)? I have started to do this, but I am finding it hard due to the large number of participants (over 100) and it doesn't seem like the most robust/professional way of doing it.

I've tried looking this up but feel like I am missing something - is there an obvious solution to this or should I keep manually combining the data from time 1 and time 2 according to the main variables of interest?

If it helps to also know this, I plan to use a combination of independent t-tests, ANOVAs, chi square and MANOVAs on the data once it is combined (comparing time 1 and time 2).

Thank you very much for any advice you can give me.

[Mahi]

Hi,

I think the only solution I think is to make the variable names identical in both the datasets and then try merging instead of copy pasting the data. Also renaming of the variables takes less time than to copy paste each dataset below the other, which also involves identifying the variables that are to be matched.

If still there are any extra variables in any of the datasets, then the cases with missing data points will be created in the datapart where these variables were not present.

I will also check if there is any other method. That is if we have a method of changing the variable names at the time of merging itself, to make the life easy.

Mahi..