To reveal the attack pattern, terrorism groups which attacked more than 500 events were empirically studied. Under the hypothesis that their interevent time follow power-law distribution, the maximum-likelihood estimation was applied to estimate the power-law exponent, and then the Kolmogorov-Smirnov（KS) statistic was used to test the hypothesis. The results show that the interevent time distributions of all the groups are power-law; The burst of terrorism attacks has no relationship with the foundation time and the lifetime; There is no positive correlation between average activity and power-law exponent and the group size is the main factor to affect it.
ZHAO Fadong
,
ZHUANG Hongwei
,
JIN Zhenxing
. Empirical Studies on Attack Patterns of Terrorism Groups Based on MLE[J]. Complex Systems and Complexity Science, 2014
, 11(4)
: 19
-22
.
DOI: 10.13306/j.1672-3813.2014.04.004
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