https://communities.sas.com/t5/Statistical-Procedures/Proc-genmod-how-to-resolve-error-messages/m-p/33607#M1389 I have a data set that contains ~180,000 records, depicting the followup time from study recruitment until hospitalisation over a 10 year period. Hence, there are multiple records per person - each person-specific record restarts counting person time at risk from the time of release from one hospitalisation until the next hospitalisation (or study end). I am trying to determine whether the rate of hospitalisation (hosp_flag = 0/1) varies by body mass index after adjusting for age. Here's my syntax for calculating the rate of hospitalisation. <BR /> <BR /> PROC GENMOD DATA = temp1;<BR /> ODS OUTPUT ParameterEstimates = results;<BR /> CLASS bmi_cat id;<BR /> MODEL hosp_flag = bmi_cat age_year / DIST = poisson LINK = log OFFSET = logpyr TYPE3 SCALE = deviance WALD;<BR /> REPEATED subject = id / TYPE = AR; <BR /> RUN;<BR /> <BR /> The syntax is running but generating the following errors, which I think are coming from the TYPE = AR option: <BR /> <BR /> ERROR: Error in computing inverse link function.<BR /> ERROR: Error in parameter estimate covariance computation.<BR /> ERROR: Error in estimation routine.<BR /> <BR /> The same errors arise if I specify TYPE as exchangeable rather than autorgressive. Does someone know what I am doing wrong?<BR /> <BR /> Many thanks in advance. Tue, 19 May 2009 07:42:54 GMT deleted_user 2009-05-19T07:42:54Z https://communities.sas.com/t5/Statistical-Procedures/Proc-genmod-how-to-resolve-error-messages/m-p/33607#M1389 I have a data set that contains ~180,000 records, depicting the followup time from study recruitment until hospitalisation over a 10 year period. Hence, there are multiple records per person - each person-specific record restarts counting person time at risk from the time of release from one hospitalisation until the next hospitalisation (or study end). I am trying to determine whether the rate of hospitalisation (hosp_flag = 0/1) varies by body mass index after adjusting for age. Here's my syntax for calculating the rate of hospitalisation. <BR /> <BR /> PROC GENMOD DATA = temp1;<BR /> ODS OUTPUT ParameterEstimates = results;<BR /> CLASS bmi_cat id;<BR /> MODEL hosp_flag = bmi_cat age_year / DIST = poisson LINK = log OFFSET = logpyr TYPE3 SCALE = deviance WALD;<BR /> REPEATED subject = id / TYPE = AR; <BR /> RUN;<BR /> <BR /> The syntax is running but generating the following errors, which I think are coming from the TYPE = AR option: <BR /> <BR /> ERROR: Error in computing inverse link function.<BR /> ERROR: Error in parameter estimate covariance computation.<BR /> ERROR: Error in estimation routine.<BR /> <BR /> The same errors arise if I specify TYPE as exchangeable rather than autorgressive. Does someone know what I am doing wrong?<BR /> <BR /> Many thanks in advance. Tue, 19 May 2009 07:42:54 GMT https://communities.sas.com/t5/Statistical-Procedures/Proc-genmod-how-to-resolve-error-messages/m-p/33607#M1389 deleted_user 2009-05-19T07:42:54Z https://communities.sas.com/t5/Statistical-Procedures/Proc-genmod-how-to-resolve-error-messages/m-p/33608#M1390 Hi Persistence,<BR /> <BR /> Hmmm... I suspect the problem is not in TYPE=AR option but in your response variable hosp_flag. It takes values 0 or 1 i.e. it's dichotomous, yet you say it's the rate of hospitalization and you model it with Poisson distribution... I would think that either different response variable should be used or different DIST and LINK... Tue, 19 May 2009 20:12:22 GMT https://communities.sas.com/t5/Statistical-Procedures/Proc-genmod-how-to-resolve-error-messages/m-p/33608#M1390 statsplank 2009-05-19T20:12:22Z