2 results for month: 04/2015


HRDAG Offers New R Package – dga

Much of the work we do at HRDAG involves estimating the number of undocumented deaths using a statistical technique called multiple systems estimation (MSE, described in more detail here). One of our goals is to make this class of methods more broadly available to human rights researchers. In particular, we are finding that Bayesian approaches are extremely valuable for MSE. Accordingly, we are pleased to offer a new R package called dga (“decomposable graphs approach”) that performs Bayesian model averaging for MSE. The main function in this package implements a model created by David Madigan and Jeremy York. This model was designed to ...

How many police homicides in the US? A reconsideration

(This post is co-authored by Patrick Ball and Kristian Lum.) In early March, the Bureau of Justice Statistics published a report that estimated that in the period 2003-2009 and 2011, there were approximately 7427 homicides committed by police in the US. We responded that the method the analysts used, capture-recapture with two databases, is vulnerable to underestimation if the databases exhibit positive dependence. We conduct a thorough sensitivity analysis on the original independence model as applied to the police homicides databases. We used information from several other countries where our partners created multiple databases of homicides. We ...