Abstract
Recently, the Weilbull type is assumed for life distribution, and techniques for estimation and test of mean life for the Weibull were developed. But, simple methods are available only under the assumption that shape parameter m is known. In this paper, it is shown that sample mean is useful estimator after some approximate evaluations of the variance and hence it is also practical for test of the mean life. It is worth while to note that sample mean is obtained without information of m.
