This Section Index:
is a GIS?
is a GIS?
“A geographical information system
is a group of procedures that provide data input, storage
and retrieval, mapping and spatial and attribute data to support
the decision-making of the organisation” (Grimshaw,
The relationship between GIS, computer-aided
design, computer cartography, database management and remote
sensing information systems. The inter-relationships of the
different types of software is a major attribute to the success
of GIS, since it can work together with other systems apart
from having its own unique characteristics that are not available
in the other packages.
Theoretical and practical issues are spreading
beyond mere use to incorporate the hard-scientific physical
and earth sciences approach to the more complex fuzzy concepts
identified by social-scientific theories.
Criminologists debate whether to take the
Techno-Centric or the Socio-Technic approach to crime analysis.
Whilst the Techno-Centric's dependence on Information Technology
is highly attractive, criminologists as also social scientists
and in effect require the use of IT but as a tool for understanding
Spatial analysis and its impact on social research
Crime analysis takes up different forms, from physical pin charting to use of textual documentation to use of tabular data and eventually to the use of crime statistical tools and GIS, aided by value-added modules that cater specifically for crime.
Social-scientific research to date has depended on textual and tabular data that is rarely analysed in a spatio-temporal setting. The use of spatial and temporal analysis of crime data has enabled analysts to combine different resources stored in various formats into a coherent system. With GIS technology, analyses that were not possible in the traditional sense can be identified due to ‘its ability to compare multiple geographic factors and investigate geographic correlations’ and identify the root cause of a problem (Bruce, 2002: 25). It also has the ability to unravel a complex issue that may be too difficult to investigate using conventional or paper-based methods. GIS aids researchers to generate new knowledge through the use of cross-data analysis such as land zoning and offence location through the concept of layering (connected by a common frame of reference system known as x/y coordinates).
Crime Mapping is a successful tool that can
be used for a wide range of functions including policy-making,
implementation and monitoring interventions on levels of crime
and disorder. This can be done through real-time and updated
systems that allow crime to be mapped and displayed either
on an intranet or on the internet.
Through Web-GIS functionality has enabled
users to view crime in the neighbourhood as well as report
crime on-line. Most current tools still leave much to be desired
but they are being improved to an extent that real full web-maps
will soon be regarded as the main modus operandi enabling
real-time research. The functions enable regular monitoring
and updating data, though work is still required to automatically
transform that data to information and eventually to knowledge
leading to effective policymaking.
Many authors have debated the issue of use
of crime-mapping in terms of effectiveness of the technology
to aid crime analysis and in turn crime reduction, such as
the need to go beyond the hotspot map and delve into the mechanisms
of what makes a crime (Chainey, 2004).
The ability of GIS to form an analysis based
on a what, why, who, when, where, why not and how phenomena
(W6H) outlined by CMAP has helped crime-mapping tremendously.
GIS analysts seek to investigate each of the W6H pivots to
identify patterns to reach conclusions whether correlations
exist or not. The six pivots can be investigated as follows
• what categories
of crime was committed, what routines can be identified (category
analysis), what relationships are there between crimes and
• why did a crime occur, why did the
offender partake in the crime (commonalities of a pattern
– root cause of a crime problem);
• who carried out the crime, who witnessed
the crime, who was the victim (offender and target profiling);
• when did a crime occur (temporal
• where did the crime occur, where
did the offender hail from (geographic analysis – environmental
analysis) – (opportunity and routine activity);
• how did a crime occur (deductive
approach - classification and modus operandi analysis);
• why not investigate unrelated variables
to elicit if some type of relationship exists (correlation
between data layers);
GIS has facilitated the use of any data using
both space and time as a way of producing verifiable information
on the patterning and links of crime. As indicated in the
W6H structure any data that has a link to a geocoded system
can be analysed. In this way GIS has brought to the fore situations
where previously non-spatial data (attributes) can now be
linked to a spatial dataset and that same data would be integrated
into a new GIS layer. Such a structure enables the evolution
of thematic data to geographical data (locational data based
on points on the earth) to a spatial construct (relationship
between entities based on the earth) and across a temporal
For examples of crime maps go to the Crime