In order to develop meaningful statistical control limits when applicable based upon the normal distribution, the mean and the standard deviation of a population must be known. In cases when an accurate approximation of the standard deviation is not known, the calculation of reasonable...

This article on survey methodology addresses the problem of estimating degrees of freedom values from stratified multistage designs when a small number of primary sampling units (PSUs) are selected per stratum. Due to the small number of PSUs selected, the traditional Satterthwaite-based degrees...

One of the basic questions of solar research is the nature of the Sun. We show here how the plasma nature of the Sun leads to the self-generation of solar activity. The release of magnetic, rotational, gravitational, nuclear energies and that of the gravity mode oscillations deviate from...

A new method of quantitative evaluation of teaching processes is elaborated. On the base of scores data, the method permits to evaluate efficiency of teaching within one group of students and comparative teaching efficiency in two or more groups. As basic characteristics of teaching efficiency...

In this paper, we consider multivariate models for returns on Russian equities based on normal distribution, t-distribution with scalar degrees of freedom parameter and t-distribution with vector degrees of freedom parameter. Our models capture autocorrelation, volatility clustering, dynamic...