TRUNCATION BIAS. Discourage the weaker students from writing the SATs, and, presto!, your district's College Board standings improve. Number 2 Pencil is not happy with the idea, she'd prefer that students take the test, and discover for themselves whether or not they're college material.

There is a research project in here: to what extent did tracking, years ago (when I was in high school, judge how long ago that was by a picture posted below ...) discourage many students from writing the College Boards, and does that make some of the much-ballyhooed decline in test scores an artifact of truncation bias? If I'm stating the obvious, please let me know where it's published.