To close a thread started by myself several months ago, and which came up
again last week, a new command, -mrdum- is now available on SSC (thanks to
Kit Baum). Stata 7 is required.
-mrdum- is short for "multiple response dummies". -mrdum- searches across a
varlist for integer codes and creates corresponding dummy variables. It also
displays a table summarizing the results. This program was created
specifically to deal with survey questions wherein the respondent can give
multiple responses to a single question (e.g. "Check all that apply").
Sometimes these data are coded as a series of variables with the responses
entered in the order that the respondent indicated them. With data coded
this way, however, one cannot simply tabulate the responses using commands
like -tabulate- or -table-. Rather, it is useful to have instead a set of
dummy variables and a table of frequencies.
Thanks to Nick Cox whose ministrations turned my working but rather rough
code into something more artful.
Best regards,
Lee
Lee Sieswerda, Epidemiologist
Thunder Bay District Health Unit
999 Balmoral Street
Thunder Bay, Ontario
Canada P7B 6E7
Tel: +1 (807) 625-5957
Fax: +1 (807) 623-2369
[email protected]
www.tbdhu.com
> -----Original Message-----
> From: Lee Sieswerda [SMTP:[email protected]]
> Sent: Tuesday, October 22, 2002 10:51 AM
> To: '[email protected]'
> Subject: st: RE: multiple response question
>
> I can answer part 1) of Phung's question. With regard to chi-square
> testing,
> it isn't clear, to me anyway, exactly what you would want to test. But
> with
> regard to part 1), The problem with multiple response data is that the
> respondent can choose more than one response :) To complicate things,
> some
> survey houses follow what they tell me is a marketing practice of entering
> the data in the order that the respondent gave his or her responses. One
> way
> to analyze these data is to create dummies - one dummy per possible
> response. SPSS analyzes multiple response data, but it seems to store the
> dummies as internal variables that you cannot get access to. Thus, one is
> restricted to using commands that support "multiple response sets". This
> seems typical of SPSS's closed approach.
>
> I started a thread on analyzing this sort of data quite a few months ago.
> As
> Nick Cox (who seems to have a memory like a steel trap) reminded me not so
> long ago, I had promised to post a command I wrote to generate dummy
> variables from multiple response data. I've been negligent in doing that
> up
> to now because I've been having trouble making the summary table look
> pretty
> (and because I haven't run into any more of this kind of data to motivate
> further action). Aside from this aesthetic touch, the command seems to
> work.
> I've called it -mrdum- and there is a help file. If you are less
> interested
> in creating dummy variables, Eric Zbinden's -zb_qrm- analyzes aspects of
> response order in multiple response data. Eric's command also treats
> missing
> data slightly differently.
>
> If anyone has any suggestions for making the code better, feel free to
> write
> to me privately. I would appreciate it. I'll integrate the code
> suggestions
> and then send the more aesthetically pleasing version of this command to
> Kit
> Baum to place on SSC.
>
>
>
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