Abstract
Until recently, much of the research on terrorism was theoretical, based on small-n studies. The growing availability of large-n terrorism databases has provided great opportunities for terrorism researchers to identify cases and test and develop new hypotheses that are relevant to the field. But how good is the quality of the data in these databases? And how should the researcher go about choosing between competing databases? This chapter describes the need for a framework to evaluate the quality of terrorism data. Drawing on the concept of a “criterial framework” and “best practice” criterial standards developed to bridge qualitative/quantitative and small-n/large-n divides, the chapter also proposes a set of criteria to evaluate terrorism data and uses these criteria to evaluate and compare a series of quantitative terrorism events databases.
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Notes
- 1.
When a terrorist incident in one country involves victims, targets, institutions, or citizens of another country, it is considered transnational or international and is included. The 9/11 hijackings, for example, are included as transnational terrorist incidents for at least three reasons. First, the perpetrators came from outside of the United States. Second, the victims were from over 80 countries. And third, the incidents had worldwide economic and security ramifications. The bombings of the US embassies in Kenya and Tanzania on August 7, 1998, as well as the suicide car bombings aimed at British and Jewish targets in Istanbul, Turkey on November 20, 2003, are similarly included as transnational terrorist incidents since they involve perpetrators and victims from different countries. On the other hand, the bombing of the Murrah Federal Building in Oklahoma City by Timothy McVeigh is not included since it is considered to be a purely domestic event. Similarly, bombings by the IRA in Northern Ireland are not included as transnational terrorist acts. However, IRA attacks in England would be included.
- 2.
In the 1970s and 1980s, it was not at all uncommon for terrorism databases to redefine and reclassify terrorist incidents for political reasons (Paull, 1982, p. 46; Schmid, 1983, p. 260). This practice led to wide disparities in the annual Patterns of International Terrorism report across the Ford, Carter, and Reagan administrations. For example, although only eight types of incidents were classified as terrorism under Ford, as many as 17 were classified as terrorism under Reagan. Reclassification, moreover, was applied retrospectively. As a result the 1980 Patterns of Global Terrorism report estimated that the number of worldwide terrorism incidents for the period 1968–1980 was 6,714 although only a year earlier it estimated that terrorism incidents for approximately the same time period 1968–1979 were half that number or 3,336 (Wilkinson, 1986, p.44, cited in Reid, 1997).
- 3.
It should be noted that these approaches are not uniform. Post-positivists are more likely to accept the “objective” nature of reality than interpretivists and constructionists.
- 4.
The RAND website clarifies its definition further with this excerpt from Defining Terrorism by Bruce Hoffman….We may therefore now attempt to define terrorist as the deliberate creation and exploitation of fear through violence or the threat of violence in the pursuit of political change. All terrorist acts involve violence or the threat of violence. Terrorism is specifically designed to have far-reaching psychological effects beyond the immediate victim(s) or object of the terrorist attack. It is meant to instill fear within, and thereby intimidate, a wider “target audience” that might include rival ethnic or religious group, an entire country, a national government or political party, or public opinion in general. Terrorism is designed to create power where there is none or to consolidate power where there is little. Through the publicity generated by their violence, terrorists seek to obtain the leverage, influence and power they otherwise lack to effect political change on either local or international scale.
References
Abadie, A., & Gardeazabal, J. (2003). The economic costs of conflict: A Case Study for the Basque Country. American Economic Review, 93(1), 113–132.
Brady, H. E., & Collier, D. (2004). Rethinking Social Inquiry: Diverse tools, shared standards. Berkeley: Rowman & Littlefield and Berkeley Public Policy Press.
Collier, D., Brady, H. E., & Seawright, J. (2004). Sources of leverage in causal inference: Toward an alternative view of methodology. In H. Brady & D. Collier (Eds.), Rethinking social inquiry: Diverse tools, shared standards (pp. 229–266). Berkeley: Rowman & Littlefield and Berkeley Public Policy Press.
Collier, D., & Mahon, J. E., Jr. (1993). Conceptual ‘stretching’ revisited: Adapting categories in comparative analysis. American Political Science Review, 87, 845–855.
Drakos, K. (2009). Security economics: A guide for data availability and needs. Economics of Security Working Paper 6, Berlin: Economics of Security. Retrieved July 29, 2011 from https://www.diw.de/documents/publikationen/73/diw_01.c.94892.de/diw_econsec0006.pdf.
Enders, W., & Sandler, T. (1993). The effectiveness of anti-terrorism policies: Vector-autoregression-intervention analysis. American Political Science Review, 87, 829–844.
Enders, W., & Sandler, T. (1996). Terrorism and foreign direct investment in Spain and Greece. Kyklos, 49(3), 331–352.
Enders, W., Sandler, T., & Parise, G. F. (1992). An econometric analysis of the impact of terrorism on tourism. Kyklos, 45, 531–554.
Engene, J. O. (2006). TWEED code book. Bergen: University of Bergen: Department of Comparative Politics.
Engene, J. O. (2007). Five decades of terrorism in Europe: The TWEED data set. Journal of Peace Research, 44(1), 109–121.
Fleischer, A., & Buccola, S. (2002). War, terror, and the tourism market in Israel. Applied Economics, 34(11), 1335–1343.
Fowler, W. W. (1981). Terrorism data bases: A comparison of missions methods, and systems. Retrieved July 29, 2011 from http://www.rand.org/content/dam/rand/pubs/notes/2005/N1503.pdf.
Geddes, B. (1990). How the cases you choose affect the answers you get: Selection bias in comparative politics. Political Analysis, 2, 131–150.
Gerring, J. (1999). What makes a concept good? A criterial framework for understanding concept formation in the social sciences. Polity, 31(3), 357–393.
Gerring, J. (2001). Social Science Methodology: A criterial framework. Cambridge: Cambridge University Press.
Gerring, J. (2010). Social science methodology: Tasks, strategies, criteria. Cambridge: Cambridge University Press.
Goertz, G. (2005). Social Science Concepts: A user’s guide. Princeton: Princeton University Press.
Guba, E. (1981). Criteria for assessing the trustworthiness of naturalistic inquiries. Educational Communication and Technology Journal, 29(2), 75–91.
Herman, E. S., & Chomsky, N. (1988). Manufacturing Consent. New York, NY: Pantheon.
Herrera, Y., & Devesh, K. (2007). Improving data quality: Actors, incentives and capabilities. Political Analysis, 15, 365–386.
Jenkins, B., & Johnson, J. (1975). International Terrorism: A chronology, 1968–1974. Santa Monica: Rand Corporation.
Krueger, A. B., & Laitin, D. D. (2004, May 17). Faulty terror report card. Washington Post, p. A21.
Krueger, A. B., & Laitin, D. D. (2004). Misunderestimating terrorism. Foreign Affairs. Retrieved July 29, 2011 from http://www.krueger.princeton.edu/terrorism1.html.
La Free, G. L. (2010). The global terrorism database: Accomplishments and challenges. Perspectives on Terrorism, IV(1), 24–46.
La Free, G. L. (2011). Generating terrorism event data bases: Results from the global terrorism database, 1970–2008, College Park, MD: University of Maryland.
Lazarsfeld, P., & Barfeld, A. H. (1951). Qualitative measurement in the social sciences. Classification, typologies and indices. In D. Lerner & H. Lasswell (Eds.), The Policy Sciences (pp. 155–192). Stanford: Stanford University Press.
Lieberman, E. S. (2010). Bridging the qualitative-quantitative divide: Best practices in the development of historically oriented replication databases. Annual Review of Political Science, 13, 37–59.
Merari, A. (2010). Driven to death: Psychological and social aspects of suicide terrorism. Oxford: Oxford University Press.
Mickolus, E. F. (2002). How do we know we’re winning the war against terrorists? Issues in measurement. Studies in Conflict & Terrorism, 25, 151–160.
Mickolus, E. (2003). International terrorism attributes of terrorist events (ITERATE) data codebook. Dunn Loring: Vinyard Software.
Munck, G. L., & Verkuilen, J. (2002). Measuring democracy: Evaluating alternative indices. Comparative Political Studies, 35, 5–34.
Nitsch, V., & Schumacher, D. (2004). Terrorism and international trade: An empirical investigation. European Journal of Political Economy, 20(2), 423–433.
Paull, P. (1982). International terrorism: the propaganda war. Master’s thesis, University of San Francisco.
Reid, E. O. (1997). Evolution of a body of knowledge: An analysis of terrorism research. Information Processing & Management, 33(1), 91–106.
Robson, C. (2002). Real world research: A resource for social scientists and practitioner-researchers. Malden: Blackwell Publishers.
Sandler, T., Arce, D. G., & Enders, W. E. (2008). Copenhagen consensus 2008 challenge paper: Terrorism. Retrieved July 29, 2011 from http://www.copenhagenconsensus.com/Files/Filer/CC08/Papers/0%20Challenge%20Papers/CP_Terrrorism_-_Sandler.pdf.
Sandler, T., & Enders, W. (2004). An economic perspective on transnational terrorism. European Journal of Political Economy, 20(2), 301–316.
Sandler, T., & Enders, W. (2008). Economic consequences of terrorism in developed and developing countries: An overview. In P. Keefer & N. Loayza (Eds.), Terrorism and economic development (pp. 17–47). Cambridge: Cambridge University Press.
Schmid, A. (1983). Political terrorism: A research guide to concepts, theories, databases, and literature. New Brunswick: Transaction Books.
Schmid, A. P., & Jongman, A. J. (1988). Political Terrorism: A New Guide to Actors, Authors, Concepts, Data Bases, Theories, and Literature. New Brunswick, New Jersey: Transaction Books, pp. 5–6.
Schmid, A. (2004). Statistics on terrorism: The challenge of measuring trends, global terrorism. Forum on Crime and Society, 4(1–2), 49–69.
Schmid, A., & Jongman, A. J. (2005). Political Terrorism: A new guide to actors, authors, concepts, data, theories, and literature. New Brunswick: Transaction Publishers.
Sheehan, I. S. (2007). When Terrorism and Counterterrorism Clash: The war on terrorism and the transformation of terrorist activity. Amherst: Cambria Press.
Sheehan, I. S. (2009). Has the war on terrorism changed the terrorist threat? Studies in Conflict & Terrorism, 32(8), 743–761.
START National Consortium for the Study of Terrorism and Responses to Terrorism. (2011). Codebook GTD Variables and Inclusion Criteria. Retrieved July 29, 2011 from http://www.start.umd.edu/gtd/downloads/Codebook.pdf.
Wardlaw, G. (1982). Political Terrorism. Melbourne: Press Syndicate of the University of Cambridge.
Wigle, J. (2010). Introducing the worldwide incidents tracking system (WITS). Perspectives on Terrorism, 4(1), 3–23.
Wilkinson, P. (1986). Trends in international terrorism and the American response. In L. Freedman & C. Hill (Eds.), Terrorism & International Order (pp. 37–55). London: Routledge & Kegan Paul.
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Appendix
Appendix
Definitions of Terrorism
ITERATE: For the purpose of the dataset, ITERATE defines a terrorist event as
... the use, or threat of use, of anxiety-inducing, extra-normal violence for political purposes by any individual or group, whether acting for or in opposition to established governmental authority, when such action is intended to influence the attitudes and behavior of a target group wider than the immediate victims. (Mickolus, 2003, p. 2)
RAND: For the RAND database terrorism is defined as
…violence calculated to create an atmosphere of fear and alarm to coerce others into actions they would not otherwise undertake, or refrain from actions they desired to take. Acts of terrorism are generally directed against civilian targets. The motives of all terrorists are political, and terrorist actions are generally carried out in a way that will achieve maximum publicity. (RAND)Footnote 4
RAND specifies that terrorism is defined by the nature of the act, not by the identity of the perpetrators or the nature of the cause. For RAND the key elements are as follows:
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Violence or the threat of violence
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Calculated to create fear and alarm
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Intended to coerce certain actions
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Motive must include a political objective
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Generally directed against civilian targets
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Can be a group or an individual
GTD: GTD data for 1970–1997, collected by the Pinkerton Global Intelligence Service (PGIS) used the following definition of terrorism:
the threatened or actual use of illegal force and violence by a non state actor to attain a political, economic, religious, or social goal through fear, coercion, or intimidation. (START, 2011)
GTD Data for 1998–2007 coded incidents in a way to allow users to identify cases that met their own definition of terrorism. Using the original definition, each incident had to be an intentional act of violence or threat of violence by a non-state actor. In addition two of the following three criteria had to be met to be included.
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The act was aimed at attaining a political, economic, religious, or social goal.
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There included evidence of an intention to coerce, intimidate, or convey some other message to a larger audience (or audiences) than the immediate victims.
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The act was outside the context of legitimate warfare activities.
These criteria continued to be included for data collected in real time after 2007 (START, 2011).
WITS: For its database WITS uses the definition of terrorism prescribed in the congressional reporting statute 22 U.S.C. § 2656f (d)(2). This statute reads
…the term ‘terrorism’ means premeditated, politically motivated violence perpetrated against noncombatant targets by subnational groups or clandestine agents.
TWEED: For its database, TWEED uses the following explanation
An act of terrorism is counted an act that has inflicted personal injury or attacks against material targets (property) if the act is of a nature that could have led to personal injury or in another way would have a noticeable impact on an audience, while at the same time the act was committed to direct demands of or raise attention from others than those immediately inflicted with personal or material injury. (Engene, 2006)
For TWEED the following events are counted as “violent actions of a terrorist nature: bombings, explosions, arson, fires, rocket attacks, killings, attempted killings, abductions, kidnaps, shootings, sieges, violent actions, violent attacks, attacks and similar violent actions.” Further, the event must be brought about “by an agent that has deliberately initiated the action.” While TWEED excludes events in which the purpose might be a coup d’état, it includes events in which government authorities engage in actions against terrorist or put the public in a state of fear:
…events in which state authorities, police, secret services, military institutions, etc. are involved in actions directed against terrorists and terrorist groups are to be included. Also violent acts of state institutions directed against civilians are to be included, for instance in conjunction with demonstrations, strikes, and the like, when the state institution acts in a way that might put the public or sections of it in a state of fear. (Engene, 2006)
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Sheehan, I.S. (2012). Assessing and Comparing Data Sources for Terrorism Research. In: Lum, C., Kennedy, L. (eds) Evidence-Based Counterterrorism Policy. Springer Series on Evidence-Based Crime Policy, vol 3. Springer, New York, NY. https://doi.org/10.1007/978-1-4614-0953-3_2
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