Estimation of heritability by robust method in half-sib

In robust elementwise estimation approach, the variance components are expressed as functions of variances and covariances of sample covariance matrices in half-sib data structures. These variances and covariances were replaced by robust variances and covariances that were estimated in an elementwise manner. From the robust covariance matrices, we get robust estimates of variance components and heritability. Among the non-iterative robust estimators, biweight estimator with c=10 showed superior performance as compared to others. In the presence of outliers none of the classical methods give the reliable estimate, but the robust methods behave better than the classical estimators in terms of bias and MSE. Even in the presence of scale contamination, the estimates obtained by this method were close to parametric values.