You need to divide crime counts by population density. Otherwise you're just plotting population density.
It's an important truth that walking a mile in a high population density area puts you at a higher crime risk than walking a mile in a medium or low population density area.
Show HN: Play with an interactive heatmap of SF crime (and other cities)
41–50 of 137 posts
Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)
#42Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)
#43Earlier quoted context omitted.
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…
Parking turnover probably scales with population density. One of the reasons parking is more expensive in big cities is to encourage people to move their cars sooner. Smaller cities will have more cars that never move, where larger ones will have fewer.
Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)
#44You need to divide crime counts by population density. Otherwise you're just plotting population density.
Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)
#45Thanks for making this, it would be helpful if the city boundaries weren't so closely observed, most people don't care where the exact city lines are but have more of a feeling for the general metropolitan area as a blob
Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)
#46Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)
#47You need to divide crime counts by population density. Otherwise you're just plotting population density.
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
Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)
#48The location of the police stations seems influential. I know in Berkeley crimes without a firm location get geocoded to police HQ. Do you think that might be affecting these maps?
But thanks for the info, this is great to know for any potential future expansions. If you see any cases where this might be happening for the currently supported cities, please don't hesitate to get into contact with us :)
Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)
#49You 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…
Re: Show HN: Play with an interactive heatmap of SF crime (and other cities)
#50Very cool! Car Break-In useful for “safe to park here?”