Sample-size determination is often an important step in planning an epidemiological study. There are several approaches to determining sample size. It depends on the type of the study. Descriptive, observational and randomized controlled studies have different formulas to calculate sample size. In this article, we discuss the formulas that can help to estimate sample size in an epidemiological ...

An appropriate sample size is crucial for the success of many studies that involve a large number of comparisons. Sample size formulas for testing multiple hypotheses are provided in this paper. They can be used to determine the sample sizes required to provide adequate power while controlling familywise error rate or false discovery rate, to derive the growth rate of sample size with respect t...

The eeect of noise in a dichotomous process is studied from the Bayesian viewpoint. Winkler's approximation to the posterior distribution in the presence of noise is shown to break down badly near the limits of its application. Information loss is measured using eeective sample size. An account of the relationship between eeective sample size/information loss and sampling data is given which di...

In many areas of research, the precise measurement of hypothesized processes or variables (theoretical constructs, latent variables) poses a challenge by itself. In social sciences, unreliable measurements of people’s beliefs or intentions obviously hamper efforts to predict their behavior. Each measurement (response to an item) reflects to some extent the true score for the intended concept an...

Background: General practitioners are the first who visit burn patients and they first calculate burn size and required fluid for the patient. Error in calculation can be disastrous. The purpose of this study is to compare four methods of estimating burn size to teach students. Methods: This is a descriptive-analytic study on 37 medical students. Four methods of estimating burn percentage was t...

When using control charts to monitor manufacturing processes, Shewhart control chart is known to be useful for detecting transient shifts, while the EWMA and CUSUM charts are useful for detecting persistent shifts. The efficiency of EWMA chart in monitoring location parameter can be improved by using an auxiliary variable that is closely related to the variable of interest. In this paper, an EW...

This study analyzed the performance of cabbage marketing in Abia State, Nigeria. Specifically the study sought to: describe socio-economic characteristics of cabbage marketers; identify marketing channels of cabbage; determine marketing cost components of cabbage marketers; determine marketing margins, market share and marketing efficiency of cabbage marketers; and determine socio-economic fact...