I heard the U.S. Military has lowered the bar when it comes to accepting "Category IV" applications. Because they can't keep up with pressures from Washington over enlistment, Category IV applicants are accepted at a current rate of 12% versus a historic rate of 2%. I'd hazard a guess this has social implications as well as technical ones.
To give a general comparison of skill levels between Category I and Category 4:
This information came from this link:
http://www.slate.com/id/2133908/
"The same study of signal battalions took soldiers who had just taken advanced individual training courses and asked them to troubleshoot a faulty piece of communications gear. They passed if they were able to identify at least two technical problems. Smarts trumped training. Among those who had scored Category I on the aptitude test (in the 93-99 percentile), 97 percent passed. Among those who'd scored Category II (in the 65-92 percentile), 78 percent passed. Category IIIA: 60 percent passed. Category IIIB: 43 percent passed. Category IV: a mere 25 percent passed.
The pattern is clear: The higher the score on the aptitude test, the better the performance in the field. This is true for individual soldiers and for units. Moreover, the study showed that adding one high-scoring soldier to a three-man signals team boosted its chance of success by 8 percent (meaning that adding one low-scoring soldier boosts its chance of failure by a similar margin).
Smarter also turns out to be cheaper. One study examined how many Patriot missiles various Army air-defense units had to fire in order to destroy 10 targets. Units with Category I personnel had to fire 20 missiles. Those with Category II had to fire 21 missiles. Category IIIA: 22. Category IIIB: 23. Category IV: 24 missiles. In other words, to perform the same task, Category IV units chewed up 20 percent more hardware than Category I units. For this particular task, since each Patriot missile costs about $2 million, they also chewed up $8 million more of the Army's procurement budget.
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