Urban Planning Blog

The most densely populated block group is one in New York County, New York — 3,240 people in 0.0097 square miles, for about 330,000 per square mile. The least dense is in the North Slope Borough of Alaska — 3 people in 3,246 square miles, or one per 1,082 square miles. The Manhattan block group I mention here is 360 million times more dense than the Alaska one.

As you see, America’s population density vary over a huge range. This is the reason why the electoral maps painted red and blue paint such a skewed picture of the country’s political preferences.

Currently, I’m compiling crime rates for cities in a particular county. Although not a perfect solution, I plan to assign the crime rates measured at jurisdictional level (often city/town/village level) to the residential properties within that jurisdiction. Also, it turns out that the data available from FBI’s Uniform Crime Reports (UCR) is based on voluntary reporting by these jurisdictions and not all cities in the county have reported their numbers. Roughly 30-40% of jurisdictions have reported their numbers.

Additionally, the crimes occurring in unincorporated cities are responded to by the county police and are not supplied with no spatial context. Crimes reported by county police are in aggregate figures and include figures from different corners of their jurisdiction which often are spatially separated by dozens of miles thus assigning crime rates from a country police department to all residential properties within the county might be erroneous.

My solution - assigning crime rates to all properties within jurisdictions whose crime rates are available through FBI UCR with their corresponding figures. For properties that lie in jurisdictions that haven’t contributed to FBI’s UCR, I relate them to the nearest jurisdiction that has reported their numbers and use those crime numbers after weighting them by population of the jurisdiction they lie in.

Thoughts? Opinions? Alternate solutions

Love dabbling in real estate data? Zillow, the online real estate website is looking for a Data and Analytics Specialist. Although I’m quite well versed in ArcGIS, unfortunately my knowledge of SQL is pretty limited which is one of the important criteria for the position. As Steven Levitt says, if you get the job after reading about it on here, don’t forget to double the value of my home in their database

This is an impressive list aggregated by City-Data. It presents top 101 U.S. cities, counties, and zip codes aggregated by many subjective categories.