[jdross]

I realize how unpopular flock is, and I will first say that I have literally never personally looked into the privacy concerns. But one city you don’t see named here is SF, which has cited Flock as a primary driver of its 10x reduction in car break-ins, and 30% reduction in burglaries. Those were a quality of life plague while I lived there

[ceejayoz]

Crime's been descending from the COVID blip for a while, everywhere, Flock or otherwise. My city saw zero murders in Q1; 2021 saw ~15 by now.

In other words: https://www.youtube.com/watch?v=xSVqLHghLpw

[whimsicalism]

it's clearly not a covid effect https://www.sfchronicle.com/projects/sf-car-breakins/

[ceejayoz]

The spike in your link's chart clearly starts in early 2020.

And "While our data extends only to 2018" is... important, yeah?

[whimsicalism]

i encourage other people reading to look at the chart so they can assess the veracity of ^ comment

[ceejayoz]

Here it is.

https://imgur.com/a/FK3sfna

There's an enormous drop in edit: late 2019, and the second drop starts in 2023.

https://www.sanfranciscopolice.org/your-sfpd/policies/depart...

> Starting on March 19, 2024, Flock Safety began installing ALPR cameras in various strategic locations across San Francisco. This rollout is expected to take place over the next 90 days. Per 19B ALPR policy, the administration of the Flock ALPR system is the responsibility of the Investigations Bureau.

How did the Flock cameras cause two crime drops before their installation?

The article's note about 2018 is talking about extending backwards, not forwards. It's entirely accurate, and a direct quote from your link.

[whimsicalism]

that drop is obviously in early 2020, not 2019 and there is no way you can look at that chart and describe car breaks ins as a "COVID blip"

[conductr]

I read this as 2020 was Covid related drop, it then returned to normal for 2 years, then began dropping again in late 2023. The covid blip is explained by what was going on at the time, nothing since 2023 has any explanation and could be flock

[ceejayoz]

COVID makes it spike up (after a months long downward trend long before the cameras), not down. Nation-wide, incidentally.

The cameras were added where the black rectangle is here: https://imgur.com/a/i00Gna0

[conductr]

There are two nearly identical peaks on this chart. The trough between them is Covid.

I’m not seeing anything I can call a Covid spike

[arjie]

The data is open, and so we don't have to do the visual reasoning off an imperfect graph. SF Chronicle has done a pretty rare (but I think good journalistic practice) of specifying the source of the data: https://data.sfgov.org/Public-Safety/Police-Department-Incid...

First to match the graph you make sure you pick 'Larceny - From Vehicle' only (there are some others one might argue matter) and ensure you're only counting incidents once (many rows reference the same incident). That lets us recreate the original graph.

When looking at many things I like to look at seasonal effects just to see, and it doesn't look like they are significant here (but you can see the Mar 2020 drop to the next year quite easily which I like): https://wiki.roshangeorge.dev/w/images/2/2e/SFPD_Vehicle_Bre...

I also tried overlaying various line charts but that's useless for visually identifying the break.

One thing I thought would be fun is to run a changepoint algorithm blindly https://wiki.roshangeorge.dev/w/File:SFPD_Vehicle_Break-Ins_...

I like PELT because it appeals to my sensibilities (you don't say ahead of time how many changepoints you want to find - you set an energy/cost param and let it roll) and it finds that one changepoint. You can have some fun with the other algos and changing the amount of breakpoints or changing the PELT cost function. And then you can have even more fun by excluding 2020 or excluding Mar 2020 onwards or replacing it by estimates from the previous years (quite suspect considering what we're trying to do but hey we're having fun - a bunch of algos all flag Nov 2023 as some moment of truth)

Anyway, anyone curious should download the data. It's pretty straightforward to use and if I goofed up with off-by-one or whatever, you can go see for yourself.

[whimsicalism]

Your analysis also supports a covid trough, not a covid peak and certainly no covid effect. I agree with other commentators suggesting that flock cameras are not the full or even most of the story, but absolutely disagree with the GP that car break-ins are some identifiable covid phenom or that the decrease is merely a post-covid return to normalcy.

Hopefully there was nothing wrong with posting a news article with a graph instead of doing the data analysis myself.

[arjie]

I was avoiding getting into the specifics because rather than tea-leaf-reading a picture one can simply look at the numbers themselves and they cannot support anything but that the one year period immediately following the lockdowns was much lower than the surrounding years.

And I think it was great you shared the news article! For many others, analyses one does oneself are less believable. I prefer doing it myself to convince myself but I wouldn’t expect it to convince others. Here I did it because I wanted to know what the fact is and I always have trouble with picking change points on a bar graph without all the ticks marked.

I put it at this level because it feels supplemental to your link not because it’s a debunking of your comment or whatever though perhaps https://news.ycombinator.com/item?id=47690707 is the best place to do it.

[johnvanommen]

That is a heck of a graph

[QuadmasterXLII]

I could believe that perma-cameraing every inch of public space is more akin to chemo than to vitamin gummies, that SF had the city equivalent of bone cancer, and that this doesn’t mean healthy midwestern towns need Flock in any way.

[BoggleOhYeah]

Any evidence that the reduction is actually due to the cameras?

[toephu2]

Don't people tend to behave if they know the are being watched?

[chaps]

yes, people tend to act differently. not the people they're trying to afect, just random people just minding their business. but it is not an effective deterrent to things like "violent crime".

• Meta-analyses (studies that average the results of multiple studies) in the UK show that video surveillance has no statistically significant impact on crime.

• Preliminary studies on video surveillance systems in the US show little to no positive impact on crime.

https://www.aclu.org/sites/default/files/images/asset_upload...

[jmye]

I thought he asked for evidence?

[MisterTea]

> which has cited Flock as a primary driver of its 10x reduction in car break-ins, and 30% reduction in burglaries

Are there reports or studies released which explains how the flock system influenced these reductions?

[cucumber3732842]

The crime did not happen because of a lack of technological capability or resources availability at a given price point. It happened because of politics and priorities. The 1984 camera dragnet vendor is no more responsible for the change in politics and priorities and subsequent crime reduction than whatever vendor sold the tires for the cop cars.

[mixmastamyk]

ALPR does help with some things but stationary burglaries are largely not among them.

[jeffbee]

Unfortunately, Flock really has been doing some shady stuff and the alliance of 1) people with legitimate concerns about Flock operations, and 2) the much larger population of people who are accustomed to getting away with petty crimes is, together, politically successful.

It would be easy to create a camera network that is locally owned and operated by public agencies, and if any place in America could so that it should be SF.