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Solving a Marine Corps Recruiting Mystery: The ASVAB Test

In the mid-1970s, soon after the draft had ended, the Marine Corps commanding general in charge of recruit training approached CNA analyst Bill Sims with a problem. Aptitude test results reported that the latest intakes had been the brightest ever. But drill instructors saw things differently. “’The kids that are coming in today are not bad people, they're just slow, really slow,’” Sims recalls Gen. Robert Barrow saying.

The test, known as the Armed Services Vocational Aptitude Battery, or ASVAB, was relatively new. So was the notion of recruiting Marines to the all-volunteer force. Sims, who held a Ph.D. in physics, would spend the rest of the decade using analysis to solve the mystery. And eventually, he would help fix it.

Sims found that the problem was two-fold. At the low end of scores, the test was miscalibrated. Ranked in percentiles, recruits were scoring 15 to 17 percentage points above their actual results. If true, Sim’s conclusions were a major stain on the all-volunteer force, and the Office of the Secretary of Defense was skeptical that the test could be so dramatically wrong. Follow-up studies were ordered from special testing companies. They confirmed CNA’s results. By that time, the four services had recruited about 360,000 troops whose test scores should have made them ineligible.

The second problem Sims uncovered was that some recruiters were coaching their prospects on the test. He even developed a methodology to identify which recruiters were cheating, and the Marine Corps was able to root out the problem. The Corps also asked Sims to sit on a joint service working group in charge of the ASVAB. By 1980, the test was fixed and the academic quality of recruits would remain high for decades to come. The Department of the Navy awarded Sims the Distinguished Public Service Award for his analytical efforts.

Sims notes, “It’s one thing to write a study report and ship it out and say, ‘Hey, there’s an answer, boys. Take it.’ And it’s another thing to actually be there where you can make things happen. And because the Marine Corps was willing to put us in a position like that, we could do that.”