60 Steps

You can drastically underestimate the effects of your intervention if you do not take account of diffusion of benefits (Step 13). You may conclude that the intervention is not worth the effort or that it failed to suppress the problem. This is particularly true when diffusion contaminates your control group.

Three principles of this manual are: (1) it takes more than offenders to create problems; (2) people cannot offend if there is no opportunity structure to support this behavior; and (3) altering the opportunity structures can dramatically reduce problems. It follows that responses focusing on only removing offenders have limited effects on problems.

Offenders often believe that prevention measures have been brought into force before they actually have been started. This leads to what has been called the "anticipatory benefits" of prevention. Though these anticipatory effects can occur by accident, the police can make deliberate efforts to create or intensify them.

How do you know that a response caused a problem to decline? Most problems vary in intensity, even when nothing is done about them. For example, on average there are 32 vehicle thefts per week in a particular city center, but seldom are there weeks with exactly 32 thefts. Instead, 95 percent of the weeks have between 25 and 38 thefts, and in 5 percent of the weeks fewer than 25 or more than 38 thefts are recorded. Such random variation is common.

Tables are effective tools for telling a compelling story if they are made simple. But the software used to create tables adds unnecessary and distracting packaging - the lines and labels used to interpret the data - and analysts do not always organize tables in a way that makes intuitive sense.

The purpose of your work is to help people make better decisions. To assist decision-makers, you must tell a clear story that leads from an important question to possible answers and then to effective actions. To communicate effectively you need to know who your audience is and the questions they want answered. Your story has to address their particular needs. This story can be told in a written report or in an oral presentation (see Step 58).

Maps have an important role in telling compelling stories about problems. But they need to be clear to accomplish this. That is, maps must contain as much relevant information as possible and no irrelevant information. There are a number of guides to good cartographic principles available (see box and Read More).

A presentation should begin with a basic question, use a framework to move through a description of findings, and end with a set of specific conclusions (see Step 54). Graphical material should be prepared following the guidance in Steps 55 through 57. In this step we will focus on the story you are telling. In Step 59, we will look at how the presentation should be delivered, including the use of PowerPoint.

Like tables and maps, figures and charts are effective tools for conveying information, but only if they are kept simple. All figures consist of two parts packaging and content. Content is the information you are interested in conveying to others. The purpose of the packaging is to ensure that the content can be quickly, easily, and accurately interpreted. Simplicity means keeping the packaging to a minimum.

All professionals are required to make presentations, and presentation skills are becoming as important as good writing. The key to a good presentation is thorough preparation. The following points come from a variety of sources, including our own experiences - good and bad.