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Show HN: Play with an interactive heatmap of SF crime (and other cities)

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81–90 of 137 posts

Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)

#81

It's interesting to see how certain crimes (e.g. Assault and Robbery) have hotspots that map perfectly onto BART stops (16th & Mission, 24th & Mission).

The rest of the hotspots are just 2 more stations, Civic Center and Powell, too.

Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)

#84
Can anyone speak to whether public statistics are accurate or not? Can anyone reassure me that these statistics are impossible to manipulate?

I have a suspicion these statistics are only accurate and available when it is convenient for the people responsible for providing those statistics.

Isn't it the case that the police are responsible for providing statistics to the public? During the pandemic and during the George Floyd protests, there were political reasons for gathering information and using to show that A) "crime is up!" or B) "crime is actually still historically low!"

A few years ago, I was frustrated about the reporting on these statistics, and went to a variety of police web sites.

Some of the websites said: "Because of the pandemic, we are so overwhelmed by crime and everything, we cannot provide current statistics!" And, other sites said "Because of the pandemic, we are so overwhelmed by crime and everything, we cannot provide past statistics!" And, some websites just completely won't load. If a police department does not want to pay their IT person, or the company that provides it can't get their act together, the website will be down and you cannot get information directly from the police.

If you have a category of crime that is high, the police need to either fix that problem, or fix the numbers. Right?

I know that some sources of information come from the FBI. But, aren't those numbers often provided by the police?

And, in certain parts of the country were in favor of defunding the police, and certain parts of the country are filled with "Blue Lives Matters" people. Won't the police in the defund areas want to show crime is up? Won't those in regions with different sensibilities want to show their policing works? Can anyone tell me why this isn't a problem?

It is anecdotal, but aren't there areas of certain cities where the citizens have stopped reporting crimes because the police don't come anymore? How is that reflected in the numbers, if at all?

Can anyone else see a big gaping hole in how these stats are collected and used? Is there standardization across the country about these statistics?

Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)

#85

You need to divide crime counts by population density. Otherwise you're just plotting population density.

Thanks for checking out the site and for the feedback. It's definitely something we're looking into. It's kind of an interesting question though because it somewhat varies by crime category. Take car break ins, for instance - this is more of a constant factor than a population density scalar because the number of parking spots is generally fixed on a per-block basis rather than scaling with population density. I thin…

As a toggle would be useful because depending on how you're using the map you might want to see per capita or absolute numbers. (Personally I think it's more useful per capita.)

Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)

#86
post #75
post #47

Earlier quoted context omitted.

Yes and no. Not dividing by population density ~ Probability I will become a crime victim by travelling through that area Dividing by population densitiy ~ Probability that I would be a crime victim if I live in that area

> Probability I will become a crime victim by travelling through that area Still not that. P(you’re the victim) = crime count/potential victim count. Population density may not be the right number for the denominator, but you need something in there.

I could travel through a rural area with an extremely high per capita crime rate but my chances of encountering ANY person (good or bad) is low. I effectively avoid crime by avoiding people.

If you live somewhere, you are forced to be a part of the community, which subjects you to the per capita rate.

Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)

#87

Earlier quoted context omitted.

it’s not surprising if you’ve ever lived in that area

It is somewhat surprising actually. Presumably if there's an actual hotspot that police would be ever-present in the area until it dilutes out

[deleted]

Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)

#89

Earlier quoted context omitted.

Possibly because the crimes are occurring aboard the train, so the exact location of the crime is unclear?

probably not - the areas outside these bart stations are known as crime hotspots

made that mistake once and never again, not fun when it's pitch black out, you're waiting for a bus, and there are drug addicts crawling around doing weird shit

Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)

#90
post #67

@dang or other HN mods - can you help me understand why this post was so rapidly downranked? It's now on the 6th page... it's got to be the highest upvoted yet lowest ranked post submitted today. As far as I can tell there were no flags or anything. Am I missing something here?

Two things: (1) it set off the flamewar detector a.k.a. the overheated discussion detector; (2) users flagged it. https://news.ycombinator.com/newsfaq.html

this is probably the least flame-y thread about crime in SF I've ever seen on here
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