Gaussian estimation of regression and correlation parameters in longitudinal data

The moment estimate of the correlation parameters using generalized estimating equations (GEE) is not guaranteed to exist or to be feasible. We introduce the Gaussian estimation method and show that the estimate of the correlation parameters in longitudinal data setup is asymptotically unbiased and feasible. We derive the large sample properties of the regression and correlation estimates and we illustrate these estimators via real life data example.