Re:A Digital Rumor Should Never Lead to a Police Raid
by TrevorJ on Thursday September 22, 2016 @05:27PM
(#12560510)
That's an excellent point that I have not heard before, thank you for this.
Re:A Digital Rumor Should Never Lead to a Police Raid
by andreyvit on Friday September 23, 2016 @01:06AM
(#12562447)
It's a textbook case of base rate fallacy. [1]
Re:A Digital Rumor Should Never Lead to a Police Raid
by n72 on Friday September 23, 2016 @04:21AM
(#12563101)
No, it's not. BRF has two components: Generic information about the frequency of events and specific information about the case in question. The item in question doesn't contain these. The item in question is a much simpler point.
Re:A Digital Rumor Should Never Lead to a Police Raid
by voxic11 on Thursday September 22, 2016 @07:17PM
(#12561139)
It's basically deductive vs inductive reasoning.
Re:A Digital Rumor Should Never Lead to a Police Raid
by ekianjo on Friday September 23, 2016 @01:52AM
(#12562597)
> But the probability that a random person in the relevant demographic is the perpetrator is now 0.001%. The demographic contains 100,000 people and one perpetrator.
That's still a much higher probability than 1/(2 000 000) so I am not sure what is your point there to use numbers.
Re:A Digital Rumor Should Never Lead to a Police Raid
by rtpg on Friday September 23, 2016 @04:16AM
(#12563086)
the point is that it's not a useful indicator for stopping random people.
"Oh, to catch the thief we are going to stop 100000 people" sounds absurd, after all.
Of course you can use the clue to exclude a bunch of people, but were you going to go around arresting random people on the street without this? Of course not, so why do it after.
The problem is that the main true benefit of the information is to exclude people, but that isn't how people use it.
Suppose there are 2 million people in an area and you know some demographic information about the perpetrator that will allow 95% of them to be excluded. That is useful information.
But the probability that a random person in the relevant demographic is the perpetrator is now 0.001%. The demographic contains 100,000 people and one perpetrator.
The fallacy is in assuming that just because not being in the relevant demographic is enough to exclude you, that being in the relevant demographic should by itself be enough to suspect you.