Optimum Stratification of a Skewed Population

The focus of this paper is to develop a technique
of solving a combined problem of determining Optimum Strata
Boundaries(OSB) and Optimum Sample Size (OSS) of each stratum,
when the population understudy isskewed and the study variable has
a Pareto frequency distribution. The problem of determining the OSB
isformulated as a Mathematical Programming Problem (MPP) which
is then solved by dynamic programming technique. A numerical
example is presented to illustrate the computational details of the
proposed method. The proposed technique is useful to obtain OSB
and OSS for a Pareto type skewed population, which minimizes the
variance of the estimate of population mean.

• D.K. Rao
• M.G.M. Khan
• K.G. Reddy

• Stratified sampling
• Optimum strata boundaries
• Optimum sample size
• Pareto distribution
• Mathematical programming problem
• Dynamic programming technique.

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