The presence of outlying anchor items is an issue faced by many testing agencies. The decision to retain or remove an item is a difficult one, especially when the content representation of the anchor set becomes questionable by item removal decisions. Additionally, the reason for the aberrancy is not always clear, and if the performance of the…

The vertical scales of large-scale achievement tests created by using item response theory (IRT) models are mostly based on cluster (or correlated) educational data in which students usually are clustered in certain groups or settings (classrooms or schools). While such application directly violated assumption of independent sample of person in…

There has been little data collected on how much testing actually goes on in America's schools and how the results are used. So in the Spring of 2014, the Council staff developed and launched a survey of assessment practices. This report presents the findings from that survey and subsequent Council analysis and review of the data. It also offers…