Hello there,   Firstly, thank you so much - your suggested fix worked and allowed the margins call to run without issues. Apologies also for the delayed response.   Secondly, I am trying to find the marginal effects in the 'exposed' group (or the 'treatment' group), rather than averaged across the entire population. In other words, the 'effect of the treatment in the treated'. Given this, would you agree that I need to specify the variable in both margins= and within= ?   Thanks so much again. ... View more

Thanks, how do I make sure any WORK._DATA  dataset that gets created is not locked and/or not a view? Using the DEBUG gives me the below which is no more enlightening to me. I feel there is something not right with the macro itself; and not something I have done?   MLOGIC(MARGINS): %DO loop index variable I is now 3; loop will not iterate again. MPRINT(MARGINS): proc plm restore=_Fit; MPRINT(MARGINS): show covariance; MPRINT(MARGINS): ods output Cov=_Cov; SYMBOLGEN: Macro variable WITHIN resolves to exposed=1 MLOGIC(MARGINS): %IF condition %quote(&within) ne is TRUE ERROR: Variable _within is not on file WORK._POP. 46 The SAS System 09:27 Friday, July 16, 2021 MPRINT(MARGINS): score data=_Pop (where=(_within=1)) out=_Eta(rename=(Predicted=_eta)); NOTE: The SAS System stopped processing this step because of errors. WARNING: The data set WORK._ETA may be incomplete. When this step was stopped there were 0 observations and 0 variables. WARNING: Data set WORK._ETA was not replaced because this step was stopped. NOTE: PROCEDURE PLM used (Total process time): real time 0.00 seconds cpu time 0.01 seconds WARNING: Output 'Cov' was not created. Make sure that the output object name, label, or path is spelled correctly. Also, verify that the appropriate procedure options are used to produce the requested output object. For example, verify that the NOPRINT option is not used. SYMBOLGEN: Macro variable WITHIN resolves to exposed=1 MLOGIC(MARGINS): %IF condition %quote(&within) ne is TRUE MPRINT(MARGINS): score data=_Pop (where=(_within=1)) out=_Mu (rename=(Predicted=_mu )) / ilink; MPRINT(MARGINS): run;     ... View more

It works fine if I omit the within statement, but that's not the results I would like. ... View more

25 GOPTIONS ACCESSIBLE; 26 %Margins( 27 data=nsw_splbasis, 28 margins=exposed, 29 response=pih, 30 within=exposed=1, 31 class=exposed year_cat age_cat parity cob ever_smoke mother_id, 32 model=exposed _X: year_cat age_cat parity cob ever_smoke, 33 dist=poisson, 34 link=log, 35 geesubject=mother_id, 36 geecorr=exch, 37 options=diff cl); ERROR: Variable _within is not on file WORK._POP. WARNING: The data set WORK._ETA may be incomplete. When this step was stopped there were 0 observations and 0 variables. WARNING: Output 'Cov' was not created. Make sure that the output object name, label, or path is spelled correctly. Also, verify that the appropriate procedure options are used to produce the requested output object. For example, verify that the NOPRINT option is not used. ERROR: File WORK._MU.DATA does not exist. ERROR: Variable _within is not on file WORK._POP. ERROR: File WORK._MU.DATA does not exist. WARNING: The data set WORK._X may be incomplete. When this step was stopped there were 0 observations and 2 variables. ERROR: Replicates data set, _X, is empty. No data to analyze. NOTE: The MARGINS macro used 2.86 seconds. 38 39 GOPTIONS NOACCESSIBLE; 40 %LET _CLIENTTASKLABEL=; 41 %LET _CLIENTPROCESSFLOWNAME=; 42 %LET _CLIENTPROJECTPATH=; 43 %LET _CLIENTPROJECTPATHHOST=; 44 %LET _CLIENTPROJECTNAME=; 45 %LET _SASPROGRAMFILE=; 2 The SAS System 09:27 Friday, July 16, 2021 46 %LET _SASPROGRAMFILEHOST=; 47 48 ;*';*";*/;quit;run; 49 ODS _ALL_ CLOSE; 50 51 52 QUIT; RUN; Apologies, please see above. ... View more