- manuscript_v4.pdf (220k)
Making violent threats towards minorities like immigrants or homosexuals is increasingly common on the Internet. We present a method to automatically detect threats of violence using machine learn- ing. A material of 24,840 sentences from YouTube was manually anno- tatedasviolentthreatsornot,andwasusedtotrainandtestthemachine learning model. Detecting threats of violence works quit well with an error of classifying a violent sentence as not violent of about 10% when the error of classifying a non-violent sentence as violent is adjusted to 5%. The best classification performance is achieved by including features that combine specially chosen important words and the distance between those in the sentence.