For those of us who spend (spent) our days working with IQ tests, the average range was considered to be the middle 50% of the scores earned on those tests. There is also no universally accepted definition of intelligence. Responding somewhat sarcastically when asked what intelligence was some would answer "Intelligence is what the Wechsler tests measure." The point here is not to debate or opine on the nuances of cognitive assessment and the correlation of scores with real life outcomes.It might have to do with the fact that educated people recognize that there a whole lot of really smart people out there who did not attend college, etc. Only about 30% of adults in the USA have college degrees (4 year). More than twice that many would fall within one standard deviation (+/-) of the mean of a Gaussian distribution. As with all quantitative genetic traits IQ, or intelligence, displays a Gaussian distribution in all human societies. A true measure of intelligence does not require the verbal or written answering of questions, IMO. Scientists can effectively measure the intelligence of animals, and so forth. Maybe your teachers were of “average IQ” even if scoring disproportionately high on the standard test.
Although admittedly, only about 2% of adults in the USA have a Ph.D., which “theoretically” could put them beyond 2 standard deviations on the high side of the mean IQ. So, they’d be smart if those proportions coincided.
The point I was making is about judgement, whether about risk or skills, humans are pretty poor at it. Tying back to the sailors, lower skilled individuals tend to over estimate their abilities. I would not be surprised to learn that the sailors in question, if tested would be relatively low skilled sailors and low skilled weather forecasters. Over estimating one's ability can put one into difficult situations which could be life threatening.
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