Tim Lambert (deltoidblog AT gmail.com) is a computer scientist at the University of New South Wales.
Michael J. Phelps said:
Is it not possible that many unsuccessful robberies are not reported, thus not included in the NCS data?
NCS data is not based on reports, but a very extensive survey.
Consider that a person who is on the receiving end of an attempted robbery didn't loose anything [so what are they reporting?], may not consider themselves a victim [after all, the crime wasn't completed], and doesn't see what benefit there would be in spending the time reporting the attempt.
The NCS asks "did anyone try to rob you?"
On a personal note, 5 guys tried to rob me some years ago; they didn't complete the attempt [no gun, i had a knife in my hand (not the sharp end!) with my hand in my jacket pocket - they never saw it] and i never reported it - it just seemed like a waste of time [now that i'm more enlighted, perhaps i would].
If you had been asked by NCS "did anyone try to rob you?" would you have told them?
Furthermore, depending on the prevailing laws and attitudes of the area, one who drew a gun in self-defense might risk harrassement or criminal prosecution [i know women who carry illegally in New York City; reporting anything short of a shooting would be self-incriminating and undoubtedly result in a felony conviction]; thats a strong disincentive to report!
Sure, some may not believe the NCS's promise of anonymity. But we're talking about a discrepancy of a factor of 50 times. I cannot believe that 98% of defensive users would conceal it from the NCS, but tell Kleck about it.
