Category Methods

Practical guidance on research design, methodology, and data analysis for your thesis.

Phases and Principles of Test Construction

The development of a psychological test is a carefully planned process that takes place in several phases. Each phase is crucial to ensuring that the finished instrument is reliable and valid. In this article, we take a close look at the test construction phases.

Three steps to the perfect sample

Defining the right sample and target population in research can be a real challenge. Imagine that you have an exciting research question, but you are unsure whom you should actually survey. Too broad or too specific—both can cause problems.

How to Use the Wilcoxon Test: A Step-by-Step Guide in R and SPSS

Wilcoxon Test

The Wilcoxon test is a useful statistical tool that you can use when you want to compare two groups of data. Unlike some other tests, such as the t-test, the Wilcoxon test does not make strict assumptions about the distribution of the data. It is particularly helpful when the data are not normally distributed or when you have small sample sizes.