Situational prevention seeks to reduce opportunities for specific categories of crime by increasing the associated risks and difficulties and reducing the rewards. It is composed of three main elements: an articulated theoretical framework, a standard methodology for tackling specific crime problems, and a set of opportunity-reducing techniques. The theoretical framework is informed by a variety of "opportunity" theories, including the routine activity and rational choice perspectives. The standard methodology is a version of the action research paradigm in which researchers work with practitioners to analyze and define the problem, to identify and try out possible solutions, and to evaluate and disseminate the results. The opportunity-reducing techniques range from simple target hardening to more sophisticated methods of deflecting offenders and reducing inducements. Displacement of crime has not proved to be the serious problem once thought, and there is now increasing recognition that situational measu...

Situational Crime Prevention

This paper is intended as a survey in the area of network synthesis and optimum network design, which, in view of the importance and variety of the underlying applications, has attraced, since the early 1960s, much interest in the Operations Research community. Indeed, if the first models were studied in connection with telecommunication networks, the range of applications kept on getting broader and broader, including transportation networks, computer and teleprocessing networks, energy transport systems, water distribution networks, etc. However, beyond the apparent diversity of practical situations involved, most of these applications can be accounted for (modulo possibly a few minor adaptations), by a rather limited number of basic models. One of the main purposes of this paper is to provide the reader with a relevant classification of the area which will help him identify the fundamental structure of the problem (if any) he has to cope with, and relate it to already published work. In order to obtain a fairly good coverage of the matter, we have thus been led to identify three basic models aroung which the whole paper is organized: a general model using minimum cost multicommodity flows (Section 2); models in terms of tree-like networks (Section 3); models using nonsmultaneous single-commodity or multicommodity flows (Section 4). In each bcase the most important variants of the basic models have been surveyed with the purpose of providing as much information as possible concerning (a) the various contexts of applications from which the problem arose; (b) the main computational methods proposed in the literature for solving it, with emphasis on those techniques which appear at present, to be most efficient or promising.

Networks synthesis and optimum network design problems: Models, solution methods and applications

Crime in public transport covers a bewildering variety of offenses committed in forms of transport including trams, buses, subways, commuter trains, taxis, and jitneys. The targets of crime can be the system itself (as in vandalism or fare evasion), employees (as in assaults on ticket collectors), or passengers (as in pickpocketing or overcharging). A distinction must be made between crimes facilitated by overcrowding and by lack of supervision. Both are the result of financial constraints, plaguing all forms of public transport, which result in too little space for passengers at busy periods and not enough staff to supervise vehicles and facilities at other times. Many successful measures have been reported in dealing with specific crimes. More generally, much crime can be "designed out" of new subway systems and older train and bus stations, and order maintenance may be an effective transit policing strategy. Research has been less successful in determining whether transit systems spread crime from high...

Crime and Public Transport

With all due apologies to the aggregate age/crime curve, there is little denying that there is great variability between offenders and within offenders over time with respect to offending over the life course. Many persons offend, but only do so once. Others offend two or three times, and then stop. And a much smaller set of persons offend with high frequency and over longer periods of time. But much like a roller-coaster’s initial large incline to the top, participation and frequency of offending also exhibit declines over the life course until some finite (but difficult to identify without fail) endpoint. This decline in offending, is what is commonly referred to (but not always conceptually agreed upon) as desistance from crime. The topic of desistance is not necessarily a new one as it can be traced back to seminal works in the 19th century by both Quetelet (1831/1984) and Beccaria (1764/1992). However, it did not begin to take hold, at least empirically, until the Philadelphia Birth Cohort Study by Wolfgang et al. (1972/1987), who were the first to study transition probabilities and recidivism in a large sample of boys followed to late adolescence. Research on desistance, however, began to flourish after the U.S. National Research Council’s report on criminal careers (Blumstein et al., 1986), in which the Panel outlined a new paradigm that parceled out an individual’s offending career into distinct dimensions, with desistance emerging as a critical feature. Not surprisingly, much theoretical work was devoted to studying desistance, and policy-relevant discussion ensued in earnest, again not surprisingly because the justice system in general, and the correctional apparatus in particular, has a keen interest in curtailing offenders from persistent offending. Unfortunately, the study of desistance requires longitudinal data spanning at least the first two decades of life, but ideally would follow individuals much longer as antisocial behavior continues (to zig and zag) well into middle to late-middle adulthood. It was only until the last quarter century that such data sets “aged,” much like a fine wine or bourbon, and permitted such analyses both in the US and abroad. In this chapter, we provide an overview of the theoretical and conceptual issues surrounding the topic of desistance, as well as a review of the theoretical and empirical work regarding it. As well, we pay particular attention to the role of desistance in prevention, intervention, rehabilitation, and punishment programs and policies, and we highlight a few directions for empirical research. In doing so, we take a look at whether it is possible to “force the plant,” as the Gluecks (1937/1966, p. 205) wondered nearly 80 years ago, “so that benign maturation [desistance] will occur earlier than it seems to at present.”

Handbook of Crime Prevention and Community Safety

Center for Research on Information Technology and Organizations

In the fixed-charge transportation problem, a fixed charge is associated with each route that can be opened, in addition to the variable transportation cost proportional to the amount of goods shipped- This note presents an exact solution of this mixed integer programming problem by decomposing it into a master integer program and a series of transportation subprograms. To reduce the number of vertices that need to be examined, bounds are established on the maximum and minimum values of the total fixed cost, and feasibility conditions for the transportation problem are used extensively. Computational results show the method to be particularly suitable when fixed costs are large compared to variable costs. A composite algorithm based on Murty's and the author's results is proposed.

Technical Note—Exact Solution of the Fixed-Charge Transportation Problem

Robbery and assault of bus drivers in the United States increased by a factor of five between 1963 and 1968. A detailed study was, therefore, conducted to evaluate potential methods and techniques of reducing the incidence of this crime. This paper discusses the criteria used and the analysis of three of the countermeasures: exact fare, alarms, and photography.

Robbery and Assault of Bus Drivers

The history of Operations Research has been intertwined with computation and decision making. If we examine the fundamental methodologies that have become associated with operations research, we see that each has resulted from the need to make decisions, and that many of them require considerable numerical computation to obtain results that can support decision makers. Notice the phrasing that is almost ingrained in the way we think of operations research work: support decision making. We do not, as a profession, claim that we are the decision makers but we believe the importance of our work comes from helping, or supporting decision makers, in making the best choice based on the information available.

Paul Gray

Papers

Technical Note—Exact Solution of the Fixed-Charge Transportation Problem

Robbery and Assault of Bus Drivers

Introduction—Special Focus and Decision Support Systems (DSS)