This is a graduate-level course on multilevel modeling, a popular statistical approach in social, behavioral, and health sciences research. Multilevel modeling, also known as hierarchical linear ...

This course will discuss what mixed models are, why they are called "mixed" models, what is a "random factor", and why. The primary focus will be for the researcher to understand when he or she should ...

Earlier (Wainer & Lewis, 1990), we reported the initial development of a testlet-based algebra test. In this account, we provide the details of this excursion into the use of testlets. A pretest of ...