This site is run entirely by me, Jacob Kaplan. I am currently the Chief Data Scientist at Research on Policing Reform and Accountability (RoPRA) and my appointment is in the Princeton School of Public and International Affairs. I earned both my PhD and Master's degree in the crimininology department at Penn. My primary research focuses on using quasi-experimental designs to quantitatively analyze criminal justice policies. Lately, my research portfolio has been focused on the criminology of place, specifically on how physical security devices - such as outdoor lights - can affect crime. I've also studied a range of topics including whether more police officers can reduce crime, simulating whether firing "bad apples" will substantially reduce complaints against the police, examining public perceptions of the accuracy of forensic evidence, and how decriminalizing marijuana affects serious domestic violence.

I also have significant experience in the programming language R and have written the introductory R book Crime by the Numbers to teach others. I have written several R packages including ones that create dummy rows and columns, predict race from surnames, handle the FBI's crime data API, and read a common data format for government data - fixed-width ASCII files - into R.

This site makes it easy for people to analyze crime-related data. Select a page in the Data Tool dropdown to look at the type of data you're interested in.