OBJECTIVES The purpose of this study was to investigate the seroprevalence of hepatitis A virus (HAV) and hepatitis E virus (HEV) in Korea during 2005. METHODS Study subjects were selected from across Korea using a stratified multistage probability sampling design, and HAV and HEV seroprevalence was compared on the basis of sex, age, and residency. A total of 497 rural and urban people aged 1...

Scott and Smith (1969) develop estimators for linear functions from a two stage cluster sample, with their discussion repeated in many places. This discussion was reviewed in c01ed13.doc. It is note-worthy that Scott and Smith allow expressions for the variance to depend on the cluster. A similar development is given by Vallient et al.. We repeated the derivation of Vallient et al using the fin...

OBJECTIVE: To describe the sampling plan and estimation methods used to collect and analyze data in the survey Sexual Behavior and Perceptions of the Brazilian Population concerning HIV/Aids in 2005. METHODS: The study presents the decisions that were made concerning population defi nition, strata of interest to the survey and to the sampling plan, main procedures for data analysis and sample p...

BACKGROUND Traditional Lot Quality Assurance Sampling (LQAS) designs assume observations are collected using simple random sampling. Alternatively, randomly sampling clusters of observations and then individuals within clusters reduces costs but decreases the precision of the classifications. In this paper, we develop a general framework for designing the cluster(C)-LQAS system and illustrate t...

In adaptive cluster sampling, first proposed by Thompson (1990, 1992) and studied in detail by Thompson and Seber (1996), an initial sample of units is selected and, whenever the value of the variable of interest satisfies a specified condition, neighbouring units are added to the sample. The neighbourhood of a unit may be defined by spatial proximity or, in the case of human population, by soc...

The WHO/EPI cluster sampling method for immunization coverage surveys is part of the course for management training in EPI programmes. The application of this method, based on a framework of villages, is impractical in dispersed populations common in many countries in Africa. To make the method work under those circumstances leads to unacceptable bias, which tends to overestimate the real cover...

Monte Carlo methods and their subsequent simulated annealing are able to minimize general energy functions. However, the slow convergence of simulated annealing compared with more recent deterministic algorithms such as graph cuts and belief propagation hinders its popularity over the large dimensional Markov Random Field (MRF). In this paper, we propose a new efficient sampling-based optimizat...