Near Repeat calculator

Version history


Version 1.0 Released November 2007

  • Initial version release.

Version 1.1 Released June 2008

  • Changed user dialog from a user choice of iterations to users choosing a p value. This was in response to user feedback from the advisory panel on the initial release.
  • Decreased the minimum number of iterations from 50 to 20, for a minimum (exploratory) p value of 0.05.
  • Enabled subtle (mouse does not change style) links over NIJ logo (to NIJ MAPS program web site) and over Temple logo (to Temple University Criminal Justice department). Go ahead, click on the images.

Version 1.2 Released August 2008

  • Updated logical error in data entry (did not affect program functionality).

Version 1.3 Released August 2009

  • Updated minor error clearing expectedKnoxContingencyTable variable between iterations (my thanks to Brian Wyant for identifying this bug). This caused the extreme values in the lower right portion of the table to temporarily overcount event pairs. Zero impact on analyses focused on top left portion of tables, and minimal impact overall. Previous analyses that found statistically relevant findings in space-time constrained distances unaffected and still statistically valid.

 

 !    What are near repeats?
The near-repeat phenomenon states that if a location is the target of a crime (such as burglary), then locations within a relatively short distance have an increased chance of being burgled for a limited period of time.