Almost Unbiased Estimators for Population Coefficient of Variation Using Auxiliary Information
Rajesh Singh
Department of Statistics, Institute of science, Banaras Hindu University, Varanasi-221005, Uttar Pradesh, India.
Rohan Mishra
Department of Statistics, Institute of science, Banaras Hindu University, Varanasi-221005, Uttar Pradesh, India.
Anamika Kumari
Department of Statistics, Institute of science, Banaras Hindu University, Varanasi-221005, Uttar Pradesh, India.
Sunil Kumar Yadav *
Department of Statistics, Institute of science, Banaras Hindu University, Varanasi-221005, Uttar Pradesh, India.
*Author to whom correspondence should be addressed.
Abstract
The objective of the paper is to propose an almost unbiased ratio estimator for the finite coefficient of variation (CV). In this paper, we have proposed an exponential ratio type and log ratio type estimators for estimating population coefficient of variation. Two real data sets and one simulation study is carried out in support of the theoretical results. Mean squared error and Percent relative efficiency criteria is used to assess the performance of the estimators. It has been shown that the proposed class of estimators are almost unbiased up to the first order of approximation. Also proposed estimators are better in efficiency to other estimators consider in this study.
Keywords: Auxiliary information, bias, mean squared error, coefficient of variation, log type estimator