Table of Contents
ISRN Probability and Statistics
Volume 2012, Article ID 103860, 15 pages
Research Article

A Two-Parameter Ratio-Product-Ratio Estimator Using Auxiliary Information

1The Warren Alpert Medical School of Brown University, Box G-A1, Providence, RI 02912, USA
2Department of Computer Science, Mathematics and Physics, Faculty of Science and Technology, The University of the West Indiesat Cave Hill, P.O. Box 64, Cave Hill, Bridgetown, St. Michael BB11000, Barbados

Received 15 August 2012; Accepted 2 September 2012

Academic Editors: P. E. Jorgensen and V. Makis

Copyright © 2012 Peter S. Chami et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


We propose a two-parameter ratio-product-ratio estimator for a finite population mean in a simple random sample without replacement following the methodology in the studies of Ray and Sahai (1980), Sahai and Ray (1980), A. Sahai and A. Sahai (1985), and Singh and Espejo (2003).The bias and mean squared error of our proposed estimator are obtained to the first degree of approximation. We derive conditions for the parameters under which the proposed estimator has smaller mean squared error than the sample mean, ratio, and product estimators. We carry out an application showing that the proposed estimator outperforms the traditional estimators using groundwater data taken from a geological site in the state of Florida.