This study reports an analysis of the Force Concept Inventory (FCI) using item response curves (IRC)--the fraction of students selecting each response to an item as a function of their total score. Three large samples (N = 9606, 4360, and 1439) of calculus-based physics students were analyzed. These were drawn from three land-grant institutions…

Testwiseness is defined as the set of cognitive strategies used by a student that is intended to improve his or her score on a test regardless of the test's subject matter. Questions with elements that may be affected by testwiseness are common in physics assessments, even in those which have been extensively validated and widely used as…