Weighted Displacement Difference Calculator
This is a demonstration of how CRIME De-Coder can provide your agency with simple tools to conduct rigorous crime analysis.
This tool calculates the Weighted Displacement Difference, an estimate of the total number of crimes reduced given an input treated area vs control areas. See Wheeler and Ratcliffe (2018) for an empirical reference on the method and for advice on applying the method.
For brief instructions, calculate crime counts in your treated and control areas pre and post your intervention. (If you do not have displacement areas, you can insert 0's into those input fields.) Hit the Calculate button, and you will be presented with estimates of the total crime reduction, along with estimates of the standard error and a confidence interval for that crime reduction.
Weighted Displacement Difference Results (Standard Error)
WDD: ____ (____)
95% Confidence Interval: ___ to ___