Eristusvõime

Eristusvõime, often translated as discriminative ability or discrimination power, is a concept used in psychometrics and testing to describe how well a test or an item within a test can differentiate between individuals with different levels of a particular trait or ability. In essence, it measures the extent to which a test distinguishes high performers from low performers.

A high eristusvõime means that individuals who score high on the overall test or construct also tend to score high on that specific item, and conversely, those who score low on the overall test tend to score low on the item. This indicates that the item is effectively measuring what it is intended to measure and is contributing positively to the test's overall validity. Conversely, an item with low eristusvõime suggests that it is not effectively differentiating between individuals, and may even be measuring something different from the intended construct or be poorly worded.

In test development, items with low eristusvõime are often revised or discarded to improve the quality and accuracy of the assessment. Statistical methods, such as item discrimination analysis, are used to quantify eristusvõime. This analysis typically involves comparing the performance on an item between groups of individuals who scored at the top and bottom of the total test score. A significant difference in performance between these groups indicates good eristusvõime.