Winsteps: this is designed for typical educational or survey data where a set of questions, also called "test items", is administered to a sample of persons, such as students. The questions could be multiple choice or an attitude survey. This produces a rectangle of responses where each person is a row and each column is a question. Winsteps analyzes these data to produce an "ability", "attitude" or similar measure for every person and a difficulty measure for every question, along with many other diagnostic indicators.