topic Re: little's test for missing datas in Statistical Procedures

little's test for missing datas

kealnit — Tue, 12 May 2015 07:58:16 GMT

Hello,

I'm searching the method to calculate the little's test (1988) for hypothesis of MNAR.

hypot

does anyone has the answer ?

thanks !

Re: little's test for missing datas

Doc_Duke — Sat, 16 May 2015 22:02:10 GMT

Try this google search

proc MI test mcar site:sas.com

PROC MI may be able to address your question.

Re: little's test for missing datas

Rick_SAS — Thu, 21 May 2015 14:38:22 GMT

I don't think SAS implemented Little's test. However, the MNAR statement in PROC MI (SAS/STAT 13.1) performs sensitivity tests for the MAR assumption, which might be sufficient for you. In the book Multiple Imputation of Missing Data Using SAS, the authors say (p. 4) "Little (1988) presents a likelihood ratio test...that the data are MCAR.... Although useful in some special cases, this test is not sufficient to establish that the missing data mechanism is ignorable."

Re: little's test for missing datas

Thu, 21 May 2015 15:39:40 GMT

I will have to check out the Proc MI approach referenced above. Though, I just ran Little's test earlier this week using the following macro:

mcartest

Re: little's test for missing datas

Rick_SAS — Thu, 21 May 2015 17:18:12 GMT

Awesome. Who wrote the macro and where can I download it?

Re: little's test for missing datas

Thu, 21 May 2015 17:47:00 GMT

I saw the macro referenced in a couple of SAS User Group papers. One place it is located is here:

Macro Programs | Applied Missing Data .com

I also saw Yuming Ning listed as the author at another location. Though, I believe when using it, you can only use all numeric or categorical data (or perhaps numeric and categorical coded as integers). I would be interested in seeing the results from the macro compared to the results from a program where the test is built in.

How do you get at the MCAR test in Proc MI??

Side note, I have your Simulation book Rick and just upgraded to SAS 9.4. If I get a chance I would like to try running the code to simulate multiple categorical variables. I could not get it to run right before. There was an erratum in the book and my version of SAS was before the 9.3 second maintenance version. It does take much to confuse me!