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Fighting Statistical Illiteracy

Archive for January, 2010

Many planes crash

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Full gas tanks could stop many small plane crashes (AP Nov 29, 2009).
Another example of numerical exaggeration.  Turning 238 fuel-crashes in 5 years (3% of all civilian plane crashes) into “many”. 

Here’s the details: “There were 8,016 crashes of civilian planes — a category that excludes commercial and military flights — from 2004 through 2008, according to the NTSB. Pilot error is blamed in about 75 percent of those crashes, which killed 2,640 people on board. 

Comparatively, the 238 small planes that crashed because they ran out of gas isn’t a large number, but aviation experts say it shouldn’t happen at all.”

CONCLUSION:  How can 238 fuel-related crashes in five years be “many” when it is less than 3% of 8,016 civil plane crashes in five years?  Just because 238 is “too many” doesn’t make it “many.”  

The number becomes even smaller when compared with the number of private planes.  According to the FAA, there were 234,015 registered “general avaiation” aircraft in 2008.  This number excludes mainline planes (3,743), regional carriers (2,582) and cargo planes (949). If there were on average of 50 fuel-related crashes per year for the 234,000 general aviation planes, then the fuel-crash rate would be about 2 per 10,000 planes per year.

ANALYSIS:  This overtouting — this use of big words for small things — isn’t as bad as the equalling of opposites in Orwell’s 1984 where “War is Peace, Freedom is Slavery and Ignorance is Strength.”  But when anything more than one is “many”, the word becomes indistinguishable from “some” and the English language becomes less robust, less able to make useful distinctions. 

Sometimes the disuse of one word is not a great loss provided there is a cognitive substitute. See a listing of archaic words.   But when the word has no cognitive substitute, then an idea — a conceptual distinction — is lost.

According to one dictionary, Many (adjective) means “constituting or forming a large number”

This extended usage of many to include some is another example of numerical gamesmanship.

Written by schield

January 30th, 2010 at 10:55 am

Posted in 2Assembly