Hi - apologies in advance for a noob question.
I have a dataset with repeated measures of an outcome variable by subjects across time. Number of observations varies by subject.
What I want to do is understand how the variance/covariance of the outcome measure changes over time. Ideal output is a covariance matrix like the following:
Thanks in advance.
I have a dataset with repeated measures of an outcome variable by subjects across time. Number of observations varies by subject.
What I want to do is understand how the variance/covariance of the outcome measure changes over time. Ideal output is a covariance matrix like the following:
| Time 1 | Time 2 | Time 3 | |
| Time 1 | var(outcome if time==1) | ||
| Time 2 | cov(outcome if time==1, outcome if time==2) | var(outcome if time==2) | |
| Time 3 | cov(outcome if time==1, outcome if time==3) | cov(outcome if time==2, outcome if time==3) | var(outcome if time==3) |
