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by oarsinsync 2577 days ago
> > To illustrate lets imagine a really really good system that had a 0% false negative rate¹ , and a 0.000001%² false positive rate. If we were to sample the entire country looking the the FBI's most wanted we would end up with ~3290 matches, 3280 of which are going to be other people³.

> It's definitely a problem if you use the face recognition as your only criteria - but if it alerted security to pay more attention to someone or to double check their documents?

Where do you imagine this is happening? If its in an environment where papers are expected as standard (e.g. an airport), sure, this is relatively benign. If it's when you're walking through a mall and now you're being stopped and searched, how is that not bordering on harassment?

> Even with the false positive rate it's much more likely an individual identified by the system is a target than a random individual.

Much more likely than without the system, sure. Chances of it being a random individual and not the target? 99.6% (using the math above of 3280 innocents to 3290 people identified).

If a system had a failure rate of 99.6% when harassing people, I don't think I'd describe that as 'much more likely' to be a target than an innocent random.

2 comments

Wouldn't it be the same as a police officer having a board of wanted people on his desk and (mistakenly) thought a person in a mall to be one of those? He'd check their papers (sorry, I'm European) due to his hunch and decide?

I believe there is no better way to identify wanted criminals at scale, do we want to comb the streets with policemen and "harass" 10x more people in hoes of finding them?

It's not a death penalty to be checked and bothering additional 3200 people in the whole country is a ok tradeoff to find wanted person in my opinion.

It feels like you want to cripple the way police looks for criminals because they don't act very kind towards suspects. Maybe police is the problem and not surveillance?

The reality is that police mostly catch “wanted” criminals during traffic stops or at their homes, or at the homes of known associates. Or when they get arrested for other crimes. People have a way of turning up.

How would this face camera thing even work? Like, a camera identifies so-and-so and a police car rushes out immediately? That’s not really how police do stuff.

If a system identified individual has a 0.4% chance of being on the FBI most wanted, then that is 'much more likely' than an individual picked at random who has a likelihood of 1 in 30 million.