Estimation of normal variance based on balanced and unbalanced ranked set samples

In this paper we address the problem of estimation of the variance of a normal population based on a balanced as well as an unbalanced ranked set sample (RSS), which is a modification of the original RSS of McIntyre (1952). We have proposed several methods of estimation of variance by combining different unbiased between and within estimators, and compared their performances.link_to_subscribed_fulltex