Variance estimation using linear combination of tri-mean and quartiles

Using linear mean and variance technique to evaluate the pattering in random winding process

Improved ratio-type estimators of finite population variance using quartiles

In this paper we have proposed some ratio-type estimators of finite population variance using known values of parameters related to an auxiliary variable such as quartiles with their properties in simple random sampling. The suggested estimators have been compared with the usual unbiased and ratio estimators and the estimators due to [2], [12, 13, 14] and [3]. An empirical study is also carried...

A Self-starting Control Chart for Simultaneous Monitoring of Mean and Variance of Simple Linear Profiles

In many processes in real practice at the start-up stages the process parameters are not known a priori and there are no initial samples or data for executing Phase I monitoring and estimating the process parameters. In addition, the practitioners are interested in using one control chart instead of two or more for monitoring location and variability of processes. In this paper, we consider a s...

Mean and variance estimation by kriging

The aim of the paper is to derive the numerical least-squares esti-mator for mean and variance of random variable. In order to do so the following questions have to be answered: (i) what is the statistical model for the estimation procedure? (ii) what are the properties of the estimator, like optimality (in which class) or asymptotic properties? (iii) how does the estimator work in practice, ho...

Mean and Variance Estimation by Kriging

The aim of the paper is to derive the brand-new estimator for mean and variance that has only numerical approximation. In order to do so the following questions have to be answered: (i) what is the statistical model for the estimation procedure? (ii) what are the properties of the estimator, like optimality (in which class) or asymptotic properties? (iii) how does the estimator work in practice...