06-02-2018 06:17 PM - last edited on 06-02-2018 10:18 PM by Reeza
I am analyzing a data set.
I have 3 x 4 x 4 design.
Three treatments with four doses for each treatment and four sample time points for each dose. The samples are individual samples at different times (not repeated samples).
I am using Proc Mixed as under
class group dose time;
model e=dose|group|time/ outp=new;
06-02-2018 11:39 PM - edited 06-02-2018 11:40 PM
If the observations are independent--if there is no clustering, or blocking, or repeated measures on the same subject--and if the homogeneity of variances assumption is met, then there is only one source of variance in your design (which will be estimated as residual variance) and you do not need a RANDOM statement. The MIXED procedure works just fine without a RANDOM statement.