A jack knife is a pocket knife that is put to many tasks, because it's ready to hand. Often there could be a better tool for the job, such as a screwdriver, a scraper, or a can-opener, but these are not usually pocket items. In statistical terms, the expression implies making do with what's available. Another simile, of an extreme situation, is…

Several techniques have been developed for creating continuous smooth distributions of test norms. This paper describes two studies that explore the behavior of cubic splines in order to determine their appropriateness for use in test norming. The first study uses data from the Curriculum Referenced Tests of Mastery (CRTM) and employs two…

Four discrimination indices were compared, using score distributions which were normal, bimodal, and negatively skewed. The score distributions were systematically varied to represent the common circumstances of a military training situation using criterion-referenced mastery tests. Three 20-item tests were administered to 110 simulated subjects.…