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Santa Cruz, California bans predictive policing in U.S. first

reuters.com

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Re: Santa Cruz, California bans predictive policing in U.S. first

#261

Post by ncallaway »

iguy wrote: post #214
TallGuyShort wrote: post #174

Earlier quoted context omitted.

If crime being caught by a drive-by patrol is a significant way in which crime is being caught, to me that screams "victimless crimes". I break victimless laws all the time, sometimes with my police officer friends and neighbors present, sometimes on private property miles from any public roads. I never seem to get busted for it. So if 10-block patrols of "troubled areas" really saw an increase in enforcement action,…

If what you describe was the pattern, then the regions with lots of observed "victimless crimes" would be uncorrelated with the regions with lots of serious crimes (e.g. from counting bullet holes down at the morgue, or from ShotSpotter). That's great, this theory makes a testable prediction. It's falsifiable. That said, I agree that the smart use of such predictions should be sensitive to this. Try to predict where…

> then the regions with lots of observed "victimless crimes" would be uncorrelated with the regions with lots of serious crimes

That doesn't seem like a strong hypothesis I would've made from the given scenario.

For example, one area that's consistent with the theory is that areas with lots of "serious crime" generate a lot of police activity, which turns up a significant amount of "observed victimless crime". That creates an expectation of a positive correlation between "serious crime" and "observed victimless crime".

Then, sure, according to that theory there might also be some areas where policing starts in an area on suspicion rather than serious crime and then we get a lot of "observed victimless crime" without as much "serious crime". That would be a negative correlation that you mentioned.

I just don't think the falsifiable hypothesis you've drawn up is one that the theory actually strongly predicts, and I don't think refuting that hypothesis necessarily refutes the theory.

Re: Santa Cruz, California bans predictive policing in U.S. first

#262

Post by Barrin92 »

dv_dt wrote: post #208
tootie wrote: post #185

Earlier quoted context omitted.

NYC has used analytics since 1993 and it's widely credited as contributing to the incredible drop in crime. I don't buy for a second that ending these kind of programs will help anything. Certainly we can decrease brutality by sending police into areas with no conflicts but that defeats the whole purpose of policing. We need effective and aggressive law enforcement as much as ever. We need to root out the worst abuse…

Crime rates nationally dropped also during the same time - and not all areas had the same analytics. It's really not clear if the reductions were from the NYC stats or in particular "agressive" law enforcement.

not only nationally, but worldwide!

https://en.wikipedia.org/wiki/Crime_drop

In Germany we have no "predictive policing" to my knowledge, and even cameras and so on are used conservatively given how privacy sensitive we ware. Yet we've seen the exact same development over recent decades.

Re: Santa Cruz, California bans predictive policing in U.S. first

#263

Post by [deleted] »

jjeaff wrote: post #229
onetimeusename wrote: post #204

Earlier quoted context omitted.

What is the claim when data is said to include systemic racism and bias? Is it that race data does indeed predict higher crime but that biased policing causes the crime rate to be misreported as higher because police only focus their attention on certain areas? Is it that police actually cause crime due to racist beliefs so that they must in some way entice crimes to be committed? Is it that crimes are equal between…

For myriad of reasons, we know clearly that controlling for no other factors, crime is higher among black populations. So to extrapolate that any one person is more likely to commit a crime because they are black is the definition of racism. It is not ok to assume that someone might be more likely guilty or more likely to commit a crime based on the color of their skin. Even if you had perfect historical data. It's j…

[deleted]

Re: Santa Cruz, California bans predictive policing in U.S. first

#264

Post by UnpossibleJim »

TallGuyShort wrote: post #174
UnpossibleJim wrote: post #154

Earlier quoted context omitted.

I have no problem with that, but why aren't these types of statistical models and curve analysis being used to deploy drive by patrols? Some of this seems like throwing out the baby with the bath water, does it not? While I agree that it's way too soon for this sort of granularity, is it too soon to have 10 block, increased presence of troubled areas helped by statistical analysis?

If crime being caught by a drive-by patrol is a significant way in which crime is being caught, to me that screams "victimless crimes". I break victimless laws all the time, sometimes with my police officer friends and neighbors present, sometimes on private property miles from any public roads. I never seem to get busted for it. So if 10-block patrols of "troubled areas" really saw an increase in enforcement action,…

What you're describing is a reform of America's drug laws, not of America's criminal prediction problem and they shouldn't be conflated. Police already use prediction models, they just do it in their heads and inaccurately with much more bias and have a harder time adjusting those bias'. I'm all for changing drug laws and trying to reduce recidivism through counseling and means other than pure imprisonment, but that's beyond the scope of this article and discussion.

Re: Santa Cruz, California bans predictive policing in U.S. first

#265

Post by chippy »

TimesOldRoman wrote: post #256

I'd be curious to see how the software accounts for a self-fulfilling prophecy of "you always find what you are looking for".

For policing if you are looking for "what areas have most violent street crime" - if for are actually looking for those areas to devote resources to and you use actual data, then you will devote resources to areas which suffer actual violent street crime.

if instead of using actual data and finding what you are looking for - the alternative is using reports from the population (unless theres some other metric you would like to use? tweets?) And this means that richer and more privileged people will report more as they have 1) more confidence and trust in the police 2) more resources to lose from criminals 3)cultural reasons, and in their own areas which means that you will devote resources to areas which have the more reports and more attention from the police. This is basically how policing worked before 25 years ago.

There is a very big, clear, and obvious reason why using data to base policing decisions on is better than using no data at all, especially as most people will think that the police has inherent biases. Data can remove biases

Re: Santa Cruz, California bans predictive policing in U.S. first

#267

Post by adwn »

bhntr3 wrote: post #245
whatshisface wrote: post #193

Earlier quoted context omitted.

To [1]: Totally abstracted from anything you said, a poll that people believe something does not in any way resemble evidence that it is true. For example, only 8% of Jehovas Witnesses[2] believe that humans evolved. Is that evidence that JWs didn't evolve? "If you don't believe this you're in the minority now" has never in history been a good argument for anything, even if you are using it to try and prove something…

Of course that's true. I wasn't so much trying to provide evidence as to point out that people who felt comfortable saying "I'm not racist but I don't think this country is racist either" should not feel comfortable socially expressing that position anymore. Social proof may not be evidence but it is powerful in changing people's minds who might not be as receptive to facts and figures. I don't mind if people believe…

> at least these days with how anti-science a segment of the population seems to be

Considering the truly abysmal track record of the social sciences [1], this seems at the very least understandable with regards to the "non-hard" sciences.

[1] https://en.wikipedia.org/wiki/Replication_crisis

Re: Santa Cruz, California bans predictive policing in U.S. first

#268

Post by godelski »

lostapathy wrote: post #251
metrokoi wrote: post #249

Earlier quoted context omitted.

Do they? What are these minor infractions that would get picked up on? Likely drug or gun charges. Most people don't own guns illegal or use illegal drugs. The only common infraction I can think of is speeding, but that's not what these criminals are being picked up for. Cops don't follow a single individual around waiting for them to go 5 over the speed limit.

It's not like cops can pull you over for simple possession of weed in your glove box. They pull people over for a traffic infraction and then find the weed, illegal gun, etc.

I once looked up the arrest records in my local area. The number one reason for arrest was "driving without a license." (with no other infractions listed). I'm not saying that this was racial profiling, but I'm not denying that people with Hispanic last names accounted for the vast majority of these arrests. I am at least implying that it is a little suspicious and maybe requires a little more nuance and closer inspection.

Re: Santa Cruz, California bans predictive policing in U.S. first

#269

Post by greenshackle2 »

google234123 wrote: post #163
riazrizvi wrote: post #134

Earlier quoted context omitted.

Why not take your Bayesian decision theory and make a trading system? Invest your farm, and you'll make millions with ideas like, if a stock just had two upticks, isn't it a good idea to put a little money into an upward trending stock . Not only will you come to understand decision theory better, behavioral prediction better, you'll get paid to do it, and nobody else will get hurt!

The stock market isn't the same thing...

To spell it out:

The stock market is anti-inductive by design. Statistical patterns that reflect market inefficiencies are supposed to disappear over time.

Most problems are not anti-inductive.

So yeah, "you can't even predict the stock market with your methods" is a pretty terrible argument against methods that were never meant to predict the stock market.

Re: Santa Cruz, California bans predictive policing in U.S. first

#270

Post by A4ET8a8uTh0 »

bhntr3 wrote: post #184

The problem with predictive policing is in the name. Inference (ML) predicts the future from the past. If the past is racist, then inference will create a racist future. Since racism is systemic[1], especially when it comes to policing, predictive policing is actively working against an anti-racist future. There may be statistical ways to factor out systemic racism. There are two reasons I don't think that works: 1.…

Is reality racist or just the data used to describe it? If the latter, I see no issue with your argument. If the former, I think we need be careful about legislating reality ( mostly because it doesn't work ).
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