Topic: Title: Computation of optimal stratum boundaries using multiple auxiliary variables Authors:  Karuna Reddy - The University of the South Pacific (Fiji) [presenting]
M G M Khan - The University of the South Pacific (Fiji)
Dinesh Rao - The University of the South Pacific (Fiji)
Abstract: The computation of determining Optimal Stratum Boundaries (OSB) based on the survey variable is not feasible in practice since the variable of interest is unavailable prior to conducting the survey. A methodology is presented to compute the OSB for a study variable based on multiple auxiliary variables, which are readily available and regressible with the study variable. The auxiliary variables used for this computational problem are estimated to follow skewed 3P Weibull distributions. The problem is formulated into a Mathematical Programming Problem (MPP) that seeks minimization of the variance of the estimated population parameter. The formulated MPP is then solved for the OSB using a dynamic programming (DP) technique. A numerical example with a real data set, aiming to estimate the Haemoglobin content in women in a national Iron Deficiency Anaemia survey, is presented to illustrate the methodology. The computational results obtained by the proposed method are compared with other univariate methods and the results reveal that it yields a substantial gain in the precision of the estimates.