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cortesofttoday at 4:40 AM0 repliesview on HN

Yes! This is about why mass surveillance and dragnets and the like are horrible. These all suffer from people not being able to understand the base rate fallacy (https://en.wikipedia.org/wiki/Base_rate_fallacy)

Even if AI facial recognition gets really really good, and is 99.999% accurate, if you use it in this way you are going to arrest more innocent people than guilty people.

If you find a suspect, who has a lot of evidence pointing to them being the criminal and you run a test that is 99.999% accurate and it tells you they are guilty, they are probably guilty.

But if you take that same test and run it against the entire population of the country, it is going to find 3500 people that match with "99.999% certainty" That gives you a 0.02% of the person being guilty.

People don't think like this, though, so they think the person must be guilty.