What is irt?

IRT stands for Item Response Theory, a statistical method used for analyzing responses to assessment items or test questions. It is based on the idea that the probability of a person giving a correct response to an item on a test depends on both the person's ability and the difficulty of the item.

IRT models can provide more accurate and detailed information about individual test-takers' abilities compared to traditional psychometric approaches. They can also help in developing more effective tests by identifying and eliminating biased or poorly performing items.

IRT has applications in various fields, including educational testing, psychological assessments, and market research. It is widely used in computerized adaptive testing, where the difficulty of test items is tailored to the ability of the test-taker to efficiently determine their proficiency level.

Overall, IRT is a powerful tool for improving the quality and reliability of assessments and tests.