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NCJ Number: 69569 Add to Shopping cart Find in a Library
Title: Poisson Model of Incidents of International Terrorism in the United States
Journal: Terrorism  Volume:4  Issue:1-4  Dated:(1980)  Pages:259-265
Author(s): J M Gleason
Date Published: 1980
Page Count: 7
Sponsoring Agency: National Institute of Justice/
Rockville, MD 20849
NCJRS Photocopy Services
Rockville, MD 20849-6000
Sale Source: National Institute of Justice/
NCJRS paper reproduction
Box 6000, Dept F
Rockville, MD 20849
United States of America

NCJRS Photocopy Services
Box 6000
Rockville, MD 20849-6000
United States of America
Language: English
Country: United States of America
Annotation: Based on incidents of terrorism in the United States from 1968 to 1974, this study finds the Poisson model of terrorism to be a good model for the occurrence of international terrorist incidents.
Abstract: The Poisson model assumes (1) the probability that an event of terrorism occurs during a time interval increases with the length of the time interval, (2) the probability is almost negligible that two events of terrorism will occur in a brief time interval (with the exception of coordinated efforts), and (3) events of terrorism which occur during one time interval are generally independent of those which occur in any other time interval. Criticism of the third factor holds that an event of terrorism, if given sufficient publicity, will generate a climate which is conducive to other events of terrorism. A chronology of 507 incidents of international terrorism that took place between January 9, 1968 and April 26, 1974, was subjected to chi-square and Kolmogorov-Smirnov tests for goodness-of-fit with the Poisson model. Results support the Poisson model. With respect to observations that terrorism is a growth industry, increasing at an alarming rate for the decade 1966-76, the 76-month Poisson analysis data were subjected to simple quantitative verification, using the first 38 months to be a sample from the first half of the decade and the last 38 months to represent the second half of the decade. Findings show no increase in terrorism during this period, a result inconsistent with popular beliefs and suggesting that media coverage of terrorist incidents may be causing an incorrect perception of 'alarming' increases in terrorism in the U.S. Nine references and tables are provided.
Index Term(s): Bodyguards; Future trends; International terrorism; Models; Threat assessment; United States of America
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