|
Hi everyone,
I was wondering if anyone can help me with this problem. I have a dataset structured like this test1 test2 test3 Doz1 Doz1 Doz2 Doz3 Doz3 Doz4 Doz4 Doz4 For every person (case) I do have various results for different tests. Now, what I would like to have is a correlation matrix that looks like this: test1 Doz1 Doz2 Doz3 Doz4 Doz5 Doz1 Doz2 Doz3 Doz4 Doz5 For each test I want the correlations between my candidates. I fail in restructuring/rearranging my dataset to achieve this. Any help is therefore very much appreciated! Mark ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
|
Mark,
I don't quite understand what you are describing. >>I was wondering if anyone can help me with this problem. I have a dataset structured like this test1 test2 test3 Doz1 Doz1 Doz2 Doz3 Doz3 Doz4 Doz4 Doz4 So, are you saying that 'Doz1' is person 1, 'Doz2' is person 2? Therefore, in your example data, person 1 has two sets of scores on tests 1, 2, and 3 but that person 2 has only one set of scores. Would this be true? And, in the case of persons 1, 3 and 4, the score for test 1 is the score on the same test. Would this also be true? >>For every person (case) I do have various results for different tests. Now, what I would like to have is a correlation matrix that looks like this: test1 Doz1 Doz2 Doz3 Doz4 Doz5 Doz1 Doz2 Doz3 Doz4 Doz5 For each test I want the correlations between my candidates. OK. More questions. Correlations are defined across persons. Think about the formulas for covariance and variance. Given that, how does your request for a correlation matrix make sense? Are you giving 'correlation matrix' a different computational meaning? Also, your layout above suggests to me that you might plan to repeat the computation for test 2 and test 3. Would this be true? Lastly, some persons have multiple scores for tests 1 thru 3. How does this fact enter into the above table? All that said. You could compute the 'association' between persons across tests (Note that a 'correlation' is the association between variables, tests, in your case, across persons.) You could do that, I think, if you first did a casetovars command to restructure your dataset so that some persons had 6 tests (persons 1 and 3), some had 3 tests (person 2) and some had 9 tests (person 4). Then FLIP (the command) your dataset to interchange rows and columns. Then you'd compute correlations between persons as Correlations doz1 to doz4. Gene Maguin ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
| Free forum by Nabble | Edit this page |
