Explore local data: Crime, schools, and home prices across the nation
trulia.com
trulia.com
We're not doing per capita normalization because we haven't had that data on a per block basis, but definitely looking in to ways to start to do more granular normalization.
A bigger issue is variance in less dense areas. It looks like what you're doing today is simple counts whereas for areas with lower crime rates, more history might provide a more stable crime rate. It might also be useful to weight against a demographic prediction of crime or at least average the crime rate over the period that the demographic prediction is stable.
The purpose of this tool seems to be to decide where to live. Since the demographics of cities change over the years, what is the advantage of looking at more-past demographics?
Second, demographic instability is a very real attribute of neighborhoods, and it may be correlated with higher crime. I imagine you're trying to reduce that visibility. Why? Again, the goal is to give a current view of the crime in the area, not what the crime will look like when things calm down.
In all, I think it's good how it is, as it represents exactly what I would be looking for when I examine crime/local facilities/housing prices.
http://www.trulia.com/local/#crimes/washington-dc
PS: http://en.wikipedia.org/wiki/File:ArlingtonTODimage3.jpg High density, mixed use development is often concentrated within 1/4 to 1/2 mile from the County's Metrorail rapid transit stations, such as in Rosslyn, Courthouse, and Clarendon (shown in red from upper left to lower right). http://en.wikipedia.org/wiki/Arlington_County,_Virginia
Perhaps I don't understand ~how~ you normalized.
That fix has been made, but as I understand it our current heatmap tiles will still be in the cache until next week.
As you can see, Hunter's Point definitely sticks out in this map. http://dl.dropbox.com/u/338114/Screenshots/02l.png
Unfortunately, New York doesn't publish their crime data in a granular way. I think much of SpotCrime's data is scraped from various sources including newspapers, and we're showing what we get from them. This is a bummer for us, as it's probably not complete, but hopefully New York will publish their data soon!