It's TERRIBLE public policy for people to be pulled aside for mere physical resemblance to a third person. A person the cop's never seen, and only has a photo of, but they've been told by a computer that this is the person in the photograph.

And computers are never wrong

Even worse, they have a combinatorial explosion problem (mentioned in the "Enforce" thread above).

better technology doesn't help enough!

To oversimplify, if you have 1 error in a thousand, and you have 10,000 (crooks + innocent people), you do (10,000 * 9,999) comparisons and get 99,990,000 / 1,000 = 9,990 errors. In stats, it's a selection of every two persons out of 10,000.

It's really something like (select one of 100 crooks from 10,000 innocents), but it's still an insanely huge number of comparisons. Hoeever good your technology, adding more people will give you (N * N-1) more chances of getting an error.

Facial recognition vendors are very careful to NOT report their error rates in ways that expose this problem: it's the "elephant in the room" for that industry. And that includes Siemens, my former employer.

The German Federal security service tried this years ago in airports, and got a combinatorial explosion in false positives (AKA the "birthday paradox") that drowned out the real positives. Google knows the math, and is trying to save the inumerate from an expensive failure (;-))

When I was starting out, we had tons of women in what was a low-status industry, where programming was described as "teaching mechanical children". I think there's a broader discussion in Kraft's "Programmers and Managers" (Springer-Verlag).

And they are a moral hazard directed at police chiefs: they tempt the cheifs to push for convictions, which are measurable, instead of prevention, which isn't.

ABSTRACT
This article argues that our current laws on the topic are counterproductive, because they protect child molesters instead of bringing them to justice, they criminalize a generation of normally-behaving teenagers which diverts valuable police resources from the criminals we should be going after, and they lead to censorship and electronic book burning as well as unacceptable collateral damage to innocent families. Child abuse as such is not condoned by anybody, and this article argues that current laws are counterproductive in preventing and prosecuting it.

In http://falkvinge.net/2012/09/0... The abstract is there because the title of the article will enrage the folks doing the prosecution...

"Do one thing well" is how Unix kernel functions are written, and it's just plain a good idea. Systemd probably follows the first principle internally, many programs do.

Creating production systems[1] out of single-purpose commands connected by pipelines is a different principle, and only works if you keep them pretty simple. It's not a prionciple, but it is how a lot of Unix scripts are written, NOT including the shell that glues the parts together, and not including all the more complex programs, like ed or mail. Systemd doesn't follow the second, because it's more like ed than a text transformation like spell.

A more useful question is whether systemd as a whole does one thing, and does it well. About that, one might usefully discuss whether the Unix principle applies.

--dave
[Pipelines were patterned after a subset of "production systems" in early AI, which applied transforms to "produce" new things. They're not the kind of production systems you put on a raised floor]

You can have 99.999 accuracy, and if the number of comparisons is (N choose 2), then the probability is (N chose 2) * 0.00001, which will be (really huge number * 0.00001) which is (merely huge number).

I don't care how good or bad the implementation is, it has to have more 9's to the right of the decimal than I have zeroes to the left in the number of people, N. That's a known hard problem in computer science (;-))

--dave
[And yes, Siemens was getting crappy even then, but that isn't the problem that the FBI has to solve]

Fortunately my android already has apps for all the things I own which have "smarts". I plan to keep it that way by buying small apps from small developers.

We do this in Canada too, and it works where the number of people you're trying to recognize is small. The "birthday paradox"* says that if you're comparing 23 people, you have a 50% chance of a match. You have to multiply this by the error rate (usually much less than 2%) of a facial match program to get the false-positive rate, but it's still huge.

The German federal security service tried out Siemen's facial matcher years ago, found it had a low error rate... and was completely useless!

When you had hundreds of criminals to look for in thousands of airport passengers a day, it was directing insane numbers of people to the "capture the terrorist" queue (;-))

--dave
[*https://en.wikipedia.org/wiki/Birthday_problem]

Ok, done!

A tale told by an idiot, full of sound and fury, signifying nothing.

Engage a lawyer familiar with class actions *before* speaking to the police. You're an individual engaging in trial by battle with a huge company, and you need someone with the same degree of hitting power on your side before you start. They can advise on what's most effective in your jurisdiction. In Canada, the fraud squad is effective against enemies of moderate size. I don't see case law from them going after companies the size of a small country (;-))

The whole country is a secret: the government of the day suffered a hostile takeover by space aliens masquerading a toupees. Just have a look at any picture of the PM (;-))