The primary goal of administering a test is to assess students' abilities in the subject area. Additionally, it is crucial to understand the characteristics of the test and its items, such as item difficulty and the test's effectiveness in distinguishing between different ability levels (i.e., test reliability and item discrimination).

In this workshop, we will introduce how Classical Test Theory (CTT) and Item Response Theory (IRT) offer valuable insights into these aspects. We will talk about the methods of CTT and IRT, highlighting their key features and differences.