手法を比較

	Interrupted Time Series in Crime Analysis	Crime Displacement and Diffusion Analysis
分野	Criminology	Criminology
系統	Process / pipeline	Process / pipeline
提唱年	1980	2003
提唱者	George E. P. Box & George C. Tiao (intervention analysis); David McDowall, Richard McCleary, and colleagues (criminological text)	Kate Bowers & Shane Johnson
種類	Quasi-experimental evaluation of a policy effect on a time series	Quasi-experimental spatial impact assessment of crime prevention
原典	McDowall, D., McCleary, R., Meidinger, E. E., & Hay, R. A. (1980). Interrupted Time Series Analysis. Sage Publications. ISBN: 9780803914933	Bowers, K. J., & Johnson, S. D. (2003). Measuring the geographical displacement and diffusion of benefit effects of crime prevention activity. Journal of Quantitative Criminology, 19(3), 275–301.
別名	Crime Intervention Analysis, ITS Crime Evaluation, Quasi-Experimental Time Series for Crime, Pre-Post Crime Trend Analysis	Crime Displacement Analysis, Diffusion of Benefits Analysis, Weighted Displacement Quotient, WDQ Analysis
関連	4	4
概要	Interrupted time series (ITS) analysis evaluates whether a law, policy, or intervention changed the course of a crime series. By modeling the level and slope of crime before and after a dated 'interruption' — a gun-control law, a policing crackdown, a sentencing reform — it tests whether the series jumped or bent at that moment relative to its prior trend. Box and Tiao formalized intervention analysis in 1975, and McDowall, McCleary, and colleagues brought the method to criminology in their widely used 1980 monograph.	Displacement and diffusion analysis evaluates what happens around a crime-prevention intervention: does crime simply move to nearby areas, times, or targets (displacement), or do the benefits spill over so that crime also falls in surrounding untreated areas (diffusion of benefits)? Bowers and Johnson's weighted displacement quotient (WDQ) provides a simple, widely used metric that compares pre/post crime change in a target area, a surrounding buffer, and a control area.