3 ms·
It's something like the "rare disease" paradox in medical testing and sensitivity and specificity. If I increase the population I test to include any warm body
by avs733 6y ago
It's something like the "rare disease" paradox in medical testing and sensitivity and specificity.
If I increase the population I test to include any warm body, eventually I'll end up with more false positives than real positives.
If you are looking for one male suspect and comparing them to all the male faces (let's assume it gets gender correct) in the us, with a 99.9999% (six 9s) accurate algorithm you would get something like:
1 true positive
182,499,818 true negatives
182 false positives
Broad scale facial recognition is just an outright stupid thing to do as a sole measure of identification without the use of other information.
- Gravityloss 6y agoYes, I think in the modern world with these methods and massive data sets being used in law enforcement, medical sector etc, the people working there should undergo a lot of training about how basic Bayesian inference works etc. We are otherwise in a world of hurt. Healthy people being told they have some really serious rare diseases, maybe even starting treatment, innocent people being prosecuted or killed during raids etc.
- d6e 6y agoYeah... training almost assuredly won't happen sadly. Especially for cops.
- avs733 6y agoI teach this stuff (biomedical engineering statistics) to undergrads. The hardest thing for them with probability is false positives. conceptually it does not seem to align well with how the human brain works. I've had students literally get so frustrated the cry because they know what the math says but can't accept that you can test positive for a disease and not have it. They know they are wrong but it's just this weird sticky misconception.