Dataset simulation with missing data

[AnalytX]

Dear all,

How do you simulate datasets (longitudinal data) with missing values?

Thanking you in advance for your help,

Best,

[Reeza]

Depending on how you're simulating wouldn't you just be picking 'people' for the study from your data.  I think this is a jackknife simulation.

I'd take a sample of the data I had, with repetition, if applicable and go from there. Your real data has missing values so there shouldn't be an issue.

[Elesawey]

Hi Reeza,

I wonder if you have any information on how to simulate missing periodic (i.e. longitudinal data) in SAS. I have daily data collected from sensors and I would like to simulate scenarios when sensors are down for a long period of time (i.e. 5-15 days). Any suggestions?

Thanks. 

Mohamed

[Rick_SAS]

I think you need to provide more information. What is the mechanism for generating missing values? Is there a pattern of missing values that you are trying to simulate (see http://support.sas.com/documentation/cdl/en/statug/63962/HTML/default/viewer.htm#statug_mi_sect018.h...)? For example, missing completely at random?  Because you stated "longitudinal data," do the missing values representing censored observations?

[AnalytX]

Thanks a lot for you answers Reeza and Rick!

I am interested in different scenarii for generating missing values, including the three ones described in the link you provided Rick.