Consequence of Performance, Test, Motivation, and Mentally Taxing Items

The relation between characteristics of test takers and characteristics of items was examined in a quasi-experimental study. High-school sophomores and juniors were administered a mathematics exam that was of consequence to the sophomores but not the juniors. The juniors had more mathematics course work as a group but less motivation to perform well. Items were characterized by item difficulty (from p values), the degree to which they were mentally taxing (how much mental effort was necessary to reach a correct answer), and item position (as an index of the level of fatigue of the test taker). A differential item functioning (DIE) analysis was conducted to look at differences between sophomores and juniors on an item-by-item basis. It was found that all three item characteristic measures were related to the DIF index, with the mental taxation measure showing the strongest relation. Results are interpreted in relation to the expectancy value model of motivation as formulated by Pintrich (1988, 1989).