Contemporary educational accountability systems, including state-level systems prescribed under No Child Left Behind as well as those envisioned under the "Race to the Top" comprehensive assessment competition, rely on school-level summaries of student test scores. The precision of these score summaries is almost always evaluated using models that…

The history of generalizability theory (G theory) is told from the perspective of one researcher's experiences, describing psychometric and scientific perspectives that influenced the development of G theory and its adoption. Work that remains to be done in the field is outlined. (SLD)