I recently blogged about the Betus, Lemieux, and Kearns Monkey Cage post (based on this Kearns et al. working paper) that claimed that "U.S. media outlets disproportionately emphasize the smaller number of terrorist attacks by Muslims".
I asked Kearns and Lemieux to share their data (I could not find an email for Betus). My request was denied until the paper was published. I tweeted a few questions to the coauthors about their data, but these tweets have not yet received a reply. Later, I realized that it would be possible to recreate or at least approximate their dataset because Kearns et al. included their outcome variable coding in the appendix of their working paper. I built a dataset based on [A] their outcome variable, [B] the Global Terrorism Database that they used, and [C] my coding of whether a given perpetrator was Muslim.
My analysis indicated that these data do not appear to support the claim of disproportionate media coverage of terror attacks by Muslims. In models with no control variables, terror attacks by Muslim perpetrators were estimated to receive 5.0 times as much media coverage as other terror attacks (p=0.008), but, controlling for the number of fatalities, this effect size drops to 1.53 times as much media coverage (p=0.480), which further drops to 1.30 times as much media coverage (p=0.622) after adding a control for attacks by unknown perpetrators, so that terror attacks by Muslim perpetrators are compared to terror attacks by known perpetrators who are not Muslim. See the Stata output below, in which "noa" is the number of articles and coefficients represent incident rate ratios:
My code contains descriptions of corrections and coding decisions that I made. Data from the Global Terrorism Database is not permitted to be posted online without permission, so the code is the only information about the dataset that I am posting for now. However, the code describes how you can build your own dataset with Stata.
Below is the message that I sent to Kearns and Lemieux on March 17. Question 2 refers to the possibility that the Kearns et al. outcome variable includes news articles published before the identities of the Boston Marathon bombers were known; that lack of knowledge of who the perpetrators were makes it difficult to assign that early media coverage to the Muslim identity of the perpetrators. Question 3 refers to the fact that the coefficient on the Muslim perpetrator predictor is larger as the number of fatalities in that attack is smaller; the Global Terrorism Database lists four rows of data for the Tsarnaev case, the first of which has only one fatality, so I wanted to check to make sure that there is no error about this in the Kearns et al. data.
I created a dataset from the Global Terrorism Database and the data in the appendix of your SSRN paper. I messaged the Monkey Cage about writing a response to your post, and I received the suggestion to communicate with you about the planned response post.
For now, I have three requests:
- Can you report the number of articles in your dataset for Bobby Joe Rogers [id 201201010020] and Ray Lazier Lengend? The appendix of your paper has perpetrator Ray Lazier Lengend associated with the id for Bobby Joe Rogers.
- Can you report the earliest published date and the latest published date among the 474 articles in your dataset for the Tsarnaev case?
- Can you report the number killed in your dataset for the Tsarnaev case?
I have attached a do file that can be used to construct my dataset and run my analyses in Stata. Let me know if you have any questions, see any errors, or have any suggestions.
I have not yet received a reply to this message.
I pitched a response post to the Monkey Cage regarding my analysis, but the pitch was not accepted, at least while the Kearns et al. paper is unpublished.
 Data from the The Global Terrorism Database have this citation: National Consortium for the Study of Terrorism and Responses to Terrorism (START). (2016). Global Terrorism Database [Data file]. Retrieved from https://www.start.umd.edu/gtd.
 The method for eliminating news articles in the Kearns et al. working paper included this choice:
"We removed the following types of articles most frequently: lists of every attack of a given type, political or policy-focused articles where the attack or perpetrators were an anecdote to a larger debate, such as abortion or gun control, and discussion of vigils held in other locations."
It is worth assessing the degree to which this choice disproportionately reduces the count of articles for the Dylann Roof terror attack, which served as a background for many news articles about the display of the Confederate flag. It's not entirely clear why these types of articles should not be considered when assessing whether terror attacks by Muslims receive disproportionate media coverage.
 Controlling for attacks by unknown perpetrators, controlling for fatalities, and removing the Tsarnaev case drops the point estimate for the incident rate ratio to 0.89 (p=0.823).