When designing clinical trials, researchers often encounter the uncertainty in the treatment effect or variability assumptions. Hence the sample size calculation at the planning stage of a clinical trial may also be questionable. Adjustment of the sample size during the mid-course of a clinical trial has become a popular strategy lately. In this paper we propose a procedure for calculating addi...

Soils are highly variable at many spatial scales, which makes designing studies to accurately estimate the mean value of soil properties across space challenging. The spatial correlation structure is critical to develop robust sampling strategies (e.g., sample size and sample spacing). Current guidelines for designing studies recommend conducting preliminary investigation(s) to characterize thi...

A classical problem in neurological disorders is to understand the progression of disorder and define the trace elements (metals) which play a role in deviating a sample from normal to an abnormal state, which implies the need to create a reference knowledge base (KB) employing the control samples drawn from normal/healthy set in the context of the said neurological disorder, and in sequel to a...

We describe procedures for designing optimal and suboptimal linear detectors (discrete-time case) for additive white noise channels. We rst describe a technique for designing linear detectors based on the Wiener theory of nonlinear systems. Next, exact expressions for optimal linear detector are found when the noise amplitude's probability distribution is stable. We then describe how to computa...

This paper presents details on planning and designing human studies for Human-Robot Interaction. There is a discussion of the importance of using large sample sizes to better represent the populations being investigated in order to have a better chance of obtaining statistically significant results for small to medium effects. Coverage of the four primary methods of evaluation are presented: (1...

Reusable adaptation specifications for adaptive behaviour has come to the forefront of adaptive research recently, with EU projects such as GRAPPLE, and PhD research efforts on designing an adaptation language for learning style specification [ 28]. However, this was not the case five years ago, when an adaptation language for adaptive hypermedia (LAG) was first proposed. This paper describes t...

Recent developments in renewable energy generation make it possible for renewable sectors to supply considerable share of electricity all around the world. As these sectors get larger, more attention is paid to the implementation of supportive strategies with the aim of motivating renewable energy (RE) developers. At present, Feed-In-Tariff (FIT) policies are regarded as one of the efficient st...

This paper is designed as a tool that a researcher could use in planning and conducting quality research. This is a review paper which gives a discussion of various aspects of designing consideration in medical research. This paper covers the essentials in calculating power and sample size for a variety of applied study designs. Sample size computation for survey type of studies, observation st...

After developing a prognostic model, it is essential to evaluate the performance of the model in samples independent from those used to develop the model, which is often referred to as external validation. However, despite its importance, very little is known about the sample size requirements for conducting an external validation. Using a large real data set and resampling methods, we investig...

Statistical power is the ability to detect a significant effect, given that the effect actually exists in a population. Like most statistical concepts, statistical power tends to induce cognitive dissonance in hepatology researchers. However, planning for statistical power by an a priori sample size calculation is of paramount importance when designing a research study. There are five specific ...