%0 Journal Article %T Measuring Terrorism %A Brian Forst %A Suat Cubukcu %J Homicide Studies %@ 1552-6720 %D 2018 %R 10.1177/1088767917737808 %X This study investigates the extent of reporting and nature of biases in open-source (OS) terrorism databases. We compare OS accounts with official accounts on terrorism events in Turkey (1996-2012). Results indicate (a) substantial systematic discrepancy between OS and official accounts, which we attribute primarily to underreporting in OS accounts; (b) the discrepancy is not random¡ªincident characteristics (victim/target, offender, and incident types, temporal and spatial factors) and rational factors (especially newsworthiness) matter; and (c) severity is the strongest predictor of the probability of OS coverage %K definition of terrorism %K measurement %K media reporting of terrorism %K official accounts on terrorism %K open-source data collection %K terrorism %U https://journals.sagepub.com/doi/full/10.1177/1088767917737808