Agent-based Models of Geographical Systems

The effects of crime generators, crime attractors, and offender anchor points on the distribution of street robberies across the nearly 25,000 census blocks of Chicago are examined. The analysis includes a wide array of activities and facilities that are expected to attract criminals and generate crime. These include a variety of legal and illegal businesses and infrastructural accessibility facilitators. In addition to these crime attractors and generators, the role of the presence of motivated offenders’ anchor points, as measured by offenders’ residence and gang activity, is assessed. The analysis also includes crime attractors, crime generators, and offender anchor points in adjacent census blocks. The findings demonstrate the strength of the effects of crime generators and attractors and offender anchor points on the frequency of street robbery at the census block level.

Robberies in Chicago: A Block-Level Analysis of the Influence of Crime Generators, Crime Attractors, and Offender Anchor Points:

Motivated by empirical observations of spatio-temporal clusters of crime across a wide variety of urban settings, we present a model to study the emergence, dynamics, and steady-state properties of crime hotspots. We focus on a two-dimensional lattice model for residential burglary, where each site is characterized by a dynamic attractiveness variable, and where each criminal is represented as a random walker. The dynamics of criminals and of the attractiveness field are coupled to each other via specific biasing and feedback mechanisms. Depending on parameter choices, we observe and describe several regimes of aggregation, including hotspots of high criminal activity. On the basis of the discrete system, we also derive a continuum model; the two are in good quantitative agreement for large system sizes. By means of a linear stability analysis we are able to determine the parameter values that will lead to the creation of stable hotspots. We discuss our model and results in the context of established crim...

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A statistical model of criminal behavior

Using epidemiological techniques for testing disease contagion, it has recently been found that in the wake of a residential burglary, the risk to nearby homes is tem- porarily elevated. This paper demonstrates the ubiquity of this phenomenon by analyzing space-time patterns of burglary in 10 areas, located in five different countries. While the precise patterns vary, for all areas, houses within 200 m of a burgled home were at an elevated risk of burglary for a period of at least two weeks. For three of the five countries, differences in these patterns may partly be explained by simple differences in target density. The findings inform theories of crime concentration and offender targeting strategies, and have implications for crime forecasting and crime reduction more generally.

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Space-time patterns of risk: A cross national assessment of residential burglary victimization

This paper introduces the discrete spatial choice approach to the study of criminal target choice. The approach is used to assess whether residential burglars are attracted to target areas that are affluent, accessible, and poorly guarded. In addition, the importance of these criteria is postulated to vary across burglars. The theory is tested using data on 548 residential burglaries, committed by 290 burglars from the city of The Hague, the Netherlands. The likelihood of a neighbourhood’s being selected for burglary is heightened by its ethnic heterogeneity, its percentage of single-family dwellings, and its proximity to where the offender lives. The results and prospects of the discrete spatial choice approach for spatial target selection research are discussed. The problem of criminal location choice is a classical one in criminology. It pertains to the descriptive question of where offenders commit their offences, and to the explanatory question of why they commit them there, rather than somewhere else. In the literature, answers to the latter question have involved two general notions that have usually been dealt with separately. The first is the notion that for a crime to occur, a motivated offender must find a suitable target, in the absence of a capable guardian (Cohen and Felson 1979). The second is the notion that crimes tend to occur close to where the offender lives (Baldwin and Bottoms 1976: 78–98; Wiles and Costello 2000; Ratcliffe 2003). This paper combines these two notions, in an attempt to answer the question of how residential burglars select their target areas. For that purpose, we introduce the discrete spatial choice approach. This approach analyses target selection as being influenced by target characteristics and by offender characteristics, simultaneously. We argue that the discrete spatial choice approach is able to integrate previous findings in this field of inquiry, and is a useful theoretical and methodological tool for research in criminal target choice. In the next section, we present a review of the literature on target selection by burglars. Subsequently, we give an overview of earlier methods in the study of criminal location choice, and introduce the discrete spatial choice approach and the closely related conditional logit model. The approach is then applied to residential burglary in the city of The Hague, the Netherlands, using data from police records. The paper concludes with a summary of the main results, and a discussion of the potential and the pitfalls of the discrete spatial choice approach for studying criminal location choice. * Netherlands Institute for the Study of Crime and Law Enforcement (NSCR), PO Box 792, NL-2300 AT Leiden, The Netherlands, email: bernasco@nscr.nl or nieuwbeerta@nscr.nl, telephone: +31 71 5278527. The Haaglanden Police Force provided the crime data used in this study. We acknowledge the contributions of Rieny Albers, Hanneke van Essen, Floor Luykx (NSCR), Astrid Patty and Peter Versteegh (Haaglanden Police Force) to the collection and processing of data. We thank Richard Block, Henk Elffers, Jan de Keijser, Jasper van der Kemp and Peter van Koppen and two anonymous reviewers for constructive comments on a previous version.

How Do Residential Burglars Select Target Areas? A New Approach to the Analysis of Criminal Location Choice

This study assesses the effects of attractiveness, opportunity and accessibility to burglars on the residential burglary rates of urban neighborhoods, combining two complementary lines of investigation that have been following separate tracks in the literature. As a complement to standard measures of attractiveness and opportunity, we introduce and specify a spatial measure of the accessibility of neighborhoods to burglars. Using data on about 25, 000 attempted and completed residential burglaries committed in the period 1996–2001 in the city of The Hague, the Netherlands, we study the variation in burglary rates across its 89 residential neighborhoods. Our results suggest that all three factors, attractiveness, opportunity and accessibility to burglars, pull burglars to their target neighborhoods.

Floor Luykx

Papers

Effects of attractiveness, opportunity and accessibility to burglars on residential burglary rates of urban neighborhoods