International Journal of Statistics and Systems
  • Year: 2010
  • Volume: 5
  • Issue: 4

Towards More Efficient Estimators of the Mean Vector

  • Author:
  • Honest W. Chipoyera1, Eshetu Wencheko2
  • Total Page Count: 12
  • Page Number: 603 to 614

1School of Statistics and Actuarial Science, University of the Witwatersrand, P Bag 3, Wits 2050, Republic of South Africa e-mail: honest.chipoyera@wits.ac.za or hwchipoyera@gmail.com

2Department of Statistics, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia. e-mail: ewencheko@yahoo.com

AMS subject classification:

Abstract

The unbiased estimator of a p-variate population mean μ, the sample mean vector x¯, has traditionally been overemphasized, regardless of sample size. In this paper, alternative estimators of the parametric mean vector μ are developed. These estimators are biased and have lower mean-squared error (MSE) values. The properties of these estimators (in comparison to x¯) are explored.

Keywords

Mean-squared error, more concentrated estimator, Pitman closer estimator, sample mean vector, sample variance-covariance matrix, relative efficiency