Low statistical power undermines the purpose of scientific research; it reduces the chance of detecting a true effect. Perhaps less intuitively, low power also reduces the likelihood that a ...

The aim of this paper is to provide an overview of sample size estimations for the most frequent type of group studies that result in continuous, binary and ordered categorical outcomes. In recent ...

The probability that the null hypothesis will be rejected when it is actually true is called the false positive rate and is determined by the significance level of the test (called alpha which is ...

By Courtney Kennedy, Andrew Mercer, Scott Keeter, Nick Hatley, Kyley McGeeney and Alejandra Gimenez As the costs and nonresponse rates of traditional, probability-based surveys seem to grow each year, ...

Sampling is a technique in which samples are drawn at random (without any favor or bias). For this, suitable measures or procedures may be laid down and adopted according to the nature and ...

Whereas prior research has found that consumers’ probability judgments are sensitive to the number of categories into which a set of possible outcomes is grouped, this article demonstrates that ...

Key points Listing outcomes to find the probability of combined events Examples Questions Using sample space diagrams to find the probability of combined events Examples Question Taking a logical and ...

Adam Hayes, Ph.D., CFA, is a financial writer with 15+ years Wall Street experience as a derivatives trader. Besides his extensive derivative trading expertise, Adam is an expert in economics and ...

Let me show you a catchy new graphic and then I’ll explain what’s going on. You’ll see that, in addition to listing the date of the poll, we also list the sample size. And not only do we list the ...