What is a criterion in the context of testing?

In the context of testing, a criterion refers to the standard against which a test is assessed. This concept is crucial in psychometrics since it helps establish the validity and reliability of the test. By having a clear criterion, psychometricians can evaluate how well the test measures what it is supposed to measure.

For instance, if a test is designed to predict a job's performance, the criterion might be the actual job performance metrics of individuals who took the test. By comparing test scores to actual performance outcomes, one can determine how accurately the test predicts job effectiveness.

In essence, the criterion serves as a benchmark that allows researchers and practitioners to understand the usefulness and applicability of the test results in real-world scenarios. This concept also plays a key role in various forms of validation, such as criterion-related validity, where the relationship between test scores and the established criterion is analyzed to confirm the test's effectiveness.