Pape, Ruby and Bauer Criticize GTD Data on Suicide Terrorism

In a July 21 Monkey Cage post, Robert Pape, Kevin Ruby and Vincent Bauer criticize the Global Terrorism Database's (GTD) data that shows a recent increase in suicide terrorist attacks. As they see it:

The main trouble with the GTD is that its collection standards have changed several times, making it an inappropriate source for measuring trends. The GTD was initially funded by the DHS in 2006 and began by compiling data from three independent projects, each with its own collection methodology and standards for inclusion: one standard of collection from 1970 until 1998, another through 2008 and another through 2011. It was not until November 2011 that the GTD became responsible for collecting its own data, at which point it changed its methodology and standards. No surprise, the type and number of events in the data set changed every time the methodology changed.

The authors note that the Chicago Project on Security and Terrorism (CPOST), which has used a consistent methodology for tracking instances of suicide terrorism,  identified more instances in 2007 (the previous spike in event) than did the GTD and less in the recent couple of years (see graph here).