The first recorded use of the word military in English, spelled militarie, was in 1585. It comes from the Latin militaris (from Latin miles, meaning "soldier") through French, but is of uncertain etymology, one suggestion being derived from *mil-it- – going in a body or mass. The word is now identified as denoting someone that is skilled in use of weapons, or engaged in military service, or in warfare.
The IRT model underlying ASVAB scoring is the three-parameter logistic (3PL) model. The 3PL model represents the probability that an examinee at a given level of ability will respond correctly to an individual item with given characteristics. Specifically, the item characteristics represented in the 3PL model are difficulty, discrimination (i.e., how well the item discriminates among examinees of differing levels of ability), and guessing (i.e., the likelihood that a very low ability examinee would respond correctly simply by guessing).