After fitting a model (e.g. proc mixed) I now wish to make predictions of the mean and 95% CI using LSMEANS statement and option AT. The AT option allows many regressors but only 1 value each.   I have made an external dataset of fixed values for regressors. I would like pass each row of regressor values to the lsmeans/at statement.   Is there any way of getting the lsmeans statement (within proc mixed) to accept the matrix of regressor values? If not, and I have to (somehow) use a loop, please could you tell or point me to a resource that provides me with code for this complicated task of passing data row-by-row from an external dataset to the scalar lsmeans/at statement.   Thank you for your help. ... View more