TYPES OF CRIME MAPPING
(1) Manual Pin Mapping
Wall maps have long been a simple and useful way to depict crime incidents or hot spots. Many police departments still have large maps tacked to the wall of the briefing room with the most recent crimes represented by pins. Although useful, manual wall maps, offer limited utility because they are difficult to keep updated, keep accurate, make easy to read, and can only display a limited amount of data. (below is an example of manual pin mapping)
For example, although different colored pins could be used to represent different types of crime, date and time of incidents, the nature of incidents, and other information cannot be displayed easily. In order to update a manual wall map, for example, the pins must be removed each month. Unless a photo or some other mechanism is used to record the previous month’s map, the information illustrated on the map is lost.
Thus, a comparison is difficult, if not impossible, from one month to the next. Finally, the maps become unreadable when they display large amounts of data because of the numerous pins and/or holes.
(2) Computer Mapping
A computer map was been taken from an Internet mapping program, where an address is entered and a map of the surrounding area appears with a pin to locate the address. Even though it is possible to zoom in and out of this type of map, the geographic features (e.g., locations, streets, parks) are static and cosmetic only.
In essence, a computer map is similar to a wall map, in that the computer is used to place a point at a specific location just as a person would put a pin on a wall map. Thus, computer maps have limitations similar to wall maps. For instance, when using map an address, clicking on a point will not provide information behind that point, such as the specific address. While visually appealing and easy to use, computer mapping does not allow any more effective analysis than manual pin mapping, although the advantage is clear, because you can enlarge the image and view a REAL-TIME view when given access.
(3) The Geographic Information System (GIS)
A geographic information system (GIS) is a set of computer-based tools that allow a person to modify, visualize, query, and analyze geographic and tabular data.
A GIS is a powerful software tool that allows the user to create anything from a simple point map to a three-dimensional visualization of spatial or temporal data. A GIS is different from manual pin maps and computer maps in that it allows the analyst to view data behind the geographic features, combine various features, manipulate the data and maps, and perform statistical functions. There are many different types of GIS programs, which include desktop packages as well as a professional software
“Crime analysis mapping” is a term that has been used for the past few years to refer to research analysis using GIS in a law enforcement setting. The term crime analysis mapping is used to describe this process because using a GIS to analyze crime is not just the act of placing incidents on a map but also of analysis. Consequently, “crime analysis mapping” is the process of using a geographic information system in combination with crime analysis techniques to focus on the spatial context of criminal and other law enforcement activity.
THE GEOGRAPHIC INFORMATION SYSTEM COMPONENT:
The following is a description of the major components of a GIS, which include data representation, data features, visualization, scale, and querying. Real-world data (like illustration below – 6 data presentations) are represented by one of four features in a GIS. They include:
[1] Point Feature Data
A point feature is a discrete location that is usually depicted by a symbol or label. A point feature in the geographic information system is analogous to a pin placed on a paper wall map.
Different symbols are used to depict the location of crimes, motor vehicle accidents, traffic signs, buildings, beat stations, and cell phone towers. Depending on its use, it may depict also hot spots, comfort zones, enemy locations, its strengths, and the likes.
[2] Line Feature Data
A line feature is a geographic feature that can be represented by a line or set of lines. This map shows how different types of geographic features such as railways, streets, and rivers can be represented by a line in a GIS.
Additional examples are streams, streets, power lines, bus routes, student pathways, and lines depicting the distance from a stolen to a recovered vehicle. Line features may also include railways, large to small alleys, and pathways that can be traversed by special means or by foot.
[3] Polygon Feature Data
A polygon feature is a multisided figure represented by a closed set of lines.
It depicts the division of geographical areas or zones with valuable interests in analyzing crimes. Other examples of polygon features used in law enforcement would be patrol areas, beats, neighborhoods, or jurisdictions. Polygon features can represent areas as large as continents and as small as buildings.
[4] Image Feature Data
An image feature is a vertical photo taken from a satellite or a plane that is digitized and placed within the geographic information system coordinate system so that there are x and y coordinates associated with it. This image is an example of an aerial photograph (Google Earth could be a great example for this) that provides details of the streets, buildings, and environmental features such as landscaping are visible.
A photograph taken by spy planes is now almost obsolete for a well-developed country when drones were developed. Drones can provide a well-represented image feature if available for police purposes, it could both present an aerial or orthophotography of the place of interest.
End of CRIME MAPPING.
An independent course intended for proficiency in crime mapping would be essential for a CRIME ANALYST whose knowledge combination is information technology, statistics, and crime analysis. They are the new breed of criminologists that requires a combination of multi-disciplinal talent.
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