HOMELAND SECURITY AND DEFENSE CENTER CHILDREN AND FAMILIES The RAND Corporation is a nonprofit institution that EDUCATION AND THE ARTS helps improve policy and decisionmaking through ENERGY AND ENVIRONMENT research and analysis. HEALTH AND HEALTH CARE This electronic document was made available from INFRASTRUCTURE AND www.rand.org as a public service of the RAND TRANSPORTATION Corporation. INTERNATIONAL AFFAIRS LAW AND BUSINESS NATIONAL SECURITY Skip all front matter: Jump to Page 16 POPULATION AND AGING PUBLIC SAFETY SCIENCE AND TECHNOLOGY Support RAND Purchase this document TERRORISM AND HOMELAND SECURITY Browse Reports & Bookstore Make a charitable contribution For More Information Visit RAND at www.rand.org Explore the RAND Homeland Security and Defense Center View document details Limited Electronic Distribution Rights This document and trademark(s) contained herein are protected by law as indicated in a notice appearing later in this work. This electronic representation of RAND intellectual property is provided for non-commercial use only. Unauthorized posting of RAND electronic documents to a non-RAND website is prohibited. RAND electronic documents are protected under copyright law. Permission is required from RAND to reproduce, or reuse in another form, any of our research documents for commercial use. For information on reprint and linking permissions, please see RAND Permissions. This product is part of the RAND Corporation monograph series. RAND monographs present major research findings that address the challenges facing the public and private sectors. All RAND mono- graphs undergo rigorous peer review to ensure high standards for research quality and objectivity. Predicting Suicide Attacks Integrating Spatial, Temporal, and Social Features of Terrorist Attack Targets Walter L. Perry, Claude Berrebi, Ryan Andrew Brown, John Hollywood, Amber Jaycocks, Parisa Roshan, Thomas Sullivan, Lisa Miyashiro C O R P O R A T I O N HOMELAND SECURITY AND DEFENSE CENTER Predicting Suicide Attacks Integrating Spatial, Temporal, and Social Features of Terrorist Attack Targets Walter L. Perry, Claude Berrebi, Ryan Andrew Brown, John Hollywood, Amber Jaycocks, Parisa Roshan, Thomas Sullivan, Lisa Miyashiro Sponsored by the Naval Research Laboratory Approved for public release; distribution unlimited This research was sponsored by the Naval Research Laboratory and conducted within the RAND Homeland Security and Defense Center, a joint center of RAND Justice, Infrastructure, and Environment, and the RAND National Defense Research Institute, a federally funded research and development center sponsored by the Office of the Secretary of Defense, the Joint Staff, the Unified Combatant Commands, the Navy, the Marine Corps, the defense agencies, and the defense Intelligence Community. Library of Congress Cataloging-in-Publication Data is available for this publication. ISBN: 978-0-8330-7800-1 The RAND Corporation is a nonprofit institution that helps improve policy and decisionmaking through research and analysis. RAND’s publications do not necessarily reflect the opinions of its research clients and sponsors. R® is a registered trademark. © Copyright 2013 RAND Corporation Permission is given to duplicate this document for personal use only, as long as it is unaltered and complete. Copies may not be duplicated for commercial purposes. Unauthorized posting of RAND documents to a non-RAND website is prohibited. RAND documents are protected under copyright law. For information on reprint and linking permissions, please visit the RAND permissions page (http://www.rand.org/publications/ permissions.html). Published 2013 by the RAND Corporation 1776 Main Street, P.O. Box 2138, Santa Monica, CA 90407-2138 1200 South Hayes Street, Arlington, VA 22202-5050 4570 Fifth Avenue, Suite 600, Pittsburgh, PA 15213-2665 RAND URL: http://www.rand.org To order RAND documents or to obtain additional information, contact Distribution Services: Telephone: (310) 451-7002; Fax: (310) 451-6915; Email: [email protected] Preface This monograph documents the results of RAND’s assessment of the benefits of considering sociocultural, economic, and political factors to augment geospatial methods of predicting suicide bombings. This was a proof-of-principle effort done in conjunction with the Naval Research Laboratory and supplements its work documented in U.S. Naval Research Laboratory, 2010a. The work was conducted for the Department of Homeland Security. This research was sponsored by the Naval Research Laboratory and conducted within the RAND Homeland Security and Defense Center, a joint center of RAND Justice, Infrastructure, and Environ- ment and the RAND National Defense Research Institute, a federally funded research and development center sponsored by the Office of the Secretary of Defense, the Joint Staff, the Unified Combatant Com- mands, the Navy, the Marine Corps, the defense agencies, and the defense Intelligence Community. Questions or comments about this monograph should be sent to the project leaders, Walter Perry ([email protected]) and Claude Ber- rebi ([email protected]). For more information on the RAND Home- land Security and Defense Center, see http://www.rand.org/multi/ homeland-security-and-defense or contact the director (contact infor- mation is provided on the web page). iii Contents Preface ............................................................................. iii Figures .............................................................................vii Tables .............................................................................. ix Summary .......................................................................... xi Acknowledgments ............................................................ xxiii Abbreviations ................................................................... xxv CHaptER ONE Introduction and Overview ..................................................... 1 Background ......................................................................... 1 About This Report ................................................................. 4 CHaptER TWO Quantitative Data and Methods ............................................... 5 Quantitative Data .................................................................. 5 Socioeconomic Characteristics ................................................. 6 Demographic Characteristics ................................................... 7 Electoral Data .................................................................... 7 Proximity to Terrorist Safe Houses ............................................ 8 Sociocultural Precipitants ....................................................... 9 Principal Component Analysis and Logistic Regression .....................12 Logistic Regression .............................................................12 Dimension Reduction ..........................................................14 Classification and Regression Trees .............................................15 Sociocultural Precipitants Analysis .............................................16 Results of Quantitative Data Analysis ..........................................17 v vi Predicting Suicide Attacks Principal Components Analysis ...............................................17 Logistic Regression Models ....................................................19 Classification and Regression Trees ...........................................32 Sociocultural Precipitants ......................................................35 Summing Up ......................................................................37 CHaptER THREE Qualitative Analysis .............................................................39 Methodology ......................................................................39 Hypotheses Driving the Use of the Methodology ............................41 Assumptions in Using the Methodology ...................................... 42 Restrictions ..................................................................... 42 Timing .......................................................................... 43 Results of Qualitative Data Analysis ........................................... 43 Identification of Codes ........................................................ 44 Distribution of Codes ......................................................... 44 Retargeting of Previously Attacked Locations ...............................47 Dispersion of Attacks over Time ............................................. 48 Assessment of Transportation Targets ....................................... 50 Comparison of Codes to a Subject-Matter Expert Hypothesis ........... 50 CHaptER FOUR Conclusions and Recommendations .........................................53 Conclusions from Quantitative Data Analysis ................................53 Conclusions from Qualitative Data Analysis ................................. 54 Recommendations for Further Research .......................................55 Regression Analyses and Classification .......................................55 Sociocultural Precipitants ......................................................57 Transferability ...................................................................57 APPENDIXES A. Sociocultural Precipitant Database .......................................59 B. Logistic Regression Output ................................................71 About the Authors .............................................................. 77 Bibliography