topic Re: Propensity Score Matching in Statistical Procedures https://communities.sas.com/t5/Statistical-Procedures/Propensity-Score-Matching/m-p/207229#M11141 <HTML><HEAD></HEAD><BODY><P>The %do %while, and the data step equivalent Do While are loop constructs. They are designed to run a group of steps until a condition is matched. In your specific macro until the macro variable __num is no longer greater than or equal to 1. Or for each record in one of the data sets it is doing a large number of operations. I'm not sure, but it looks like if there are never any matches it might not have an end. This could happen if the Match_Ratio target is set too large.</P></BODY></HTML> Mon, 23 Mar 2015 16:54:37 GMT ballardw 2015-03-23T16:54:37Z Propensity Score Matching https://communities.sas.com/t5/Statistical-Procedures/Propensity-Score-Matching/m-p/207228#M11140 <HTML><HEAD></HEAD><BODY><P>Hi all, </P><P></P><P>This is my first time working with Propensity Score Matching and I've been using the attached macro, which seems to work quite well, however I have a question regarding the <STRONG>%do %while</STRONG> procedure, as I don't understand why it keeps going in <STRONG>loops</STRONG> and it takes a really long time for the execution, so far it still hasn't finished. Is it supposed to make these loops? And take a very long time (3,5 hours+)?&nbsp; I've marked with green in the attached document where the loops happen. </P><P>I would be really grateful for any help. </P><P>Thanks!</P></BODY></HTML> Sat, 21 Mar 2015 14:40:43 GMT https://communities.sas.com/t5/Statistical-Procedures/Propensity-Score-Matching/m-p/207228#M11140 SigAnn 2015-03-21T14:40:43Z Re: Propensity Score Matching https://communities.sas.com/t5/Statistical-Procedures/Propensity-Score-Matching/m-p/207229#M11141 <HTML><HEAD></HEAD><BODY><P>The %do %while, and the data step equivalent Do While are loop constructs. They are designed to run a group of steps until a condition is matched. In your specific macro until the macro variable __num is no longer greater than or equal to 1. Or for each record in one of the data sets it is doing a large number of operations. I'm not sure, but it looks like if there are never any matches it might not have an end. This could happen if the Match_Ratio target is set too large.</P></BODY></HTML> Mon, 23 Mar 2015 16:54:37 GMT https://communities.sas.com/t5/Statistical-Procedures/Propensity-Score-Matching/m-p/207229#M11141 ballardw 2015-03-23T16:54:37Z