Residuals prediction and covariance-variance
Posted: Fri Oct 05, 2012 10:27 am
Hello,
I have tried to do the prediction of the residuals at level two for intercept and slope (i.e. u0j and u1j):
Yij = b0j + b1j xij + ei
b0j= b0 + u0j
b1j= b1 + u1j
and after I have calculated cov(u0j; u1j) and var(u0j) on the predicted values. They result different from the corresponding covariance and variance obtained by the multilevel estimation. Can you help me to find why they differ?
Thanks in advance.
I have tried to do the prediction of the residuals at level two for intercept and slope (i.e. u0j and u1j):
Yij = b0j + b1j xij + ei
b0j= b0 + u0j
b1j= b1 + u1j
and after I have calculated cov(u0j; u1j) and var(u0j) on the predicted values. They result different from the corresponding covariance and variance obtained by the multilevel estimation. Can you help me to find why they differ?
Thanks in advance.