Файл: [D._Kim_Rossmo]_Geographic_Profiling(BookFi.org).pdf

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set. This approach can be of assistance in many ways, including the recon-
ciliation of varying descriptions in a series of connected crimes. Austin (1996)
used a fuzzy logic expert system for offender profiling that analyzed crime,
victim, and event details to connect rapes to rapes, and offenders to rapes.

Profiling is a useful and promising investigative methodology. It is also

a novel technique, the maturation of which requires a commitment to not
only data collection, analysis, and research, but also to operational feedback
and integration. Inductive systems require systematic methods for developing
and expanding their knowledge base. It is thus critical for scientific and
investigative methodologies to be concerned with issues of validity and reli-
ability (see Oldfield, 1995). Profiling knowledge originates from experience,
research, and statistical databases. While experience is important, if not vital,
it can also be idiosyncratic, containing limitations and unrealized biases,
upon which profiles may be based. Experience should therefore be triangu-
lated with research findings. Specification of the limitations inherent in a
method’s underlying assumptions is also important. Finally, a technique must
possess utility if it is to have value in the real world of police investigation.
Such considerations are what distinguish profiling predictions from psychic
guesses.

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Behavioural Geography

Human geography studies people and their activities, and physical geography
studies the natural environment (Goodall, 1987). While these two areas are
not unconnected, human geography is specifically concerned with three inte-
grated themes: (1) spatial analysis; (2) interrelationships between people and
the environment; and (3) regional syntheses of the first two themes. Its major
fields of study include behavioural, economic, historical, political, regional,
rural, social, transport, and urban geography.

Behavioural geography examines how people come to terms with their

physical and social environments, and uses behaviourism as a means of
understanding patterns of human spatial action. How people codify, respond
to, and react with their environments is explained in terms of cognitive
processes such as learning and stimulus-response. Those areas of behavioural
geography and the related quantitative techniques relevant for an under-
standing of crime patterns and offender spatial behaviour are discussed
below.

6.1 Movement and Distance

Perhaps the most basic heuristic in geography is the nearness principle, also
known in psychology as the least-effort principle (Zipf, 1950). A person who
is “given various possibilities for action ... will select the one requiring the
least expenditure of effort” (Reber, 1985, p. 400). This maxim describes a
great deal about the movement of people but many other factors come into
play in the psychology and behaviour of choice (Cornish & Clarke, 1986b;
Luce, 1959; Tversky & Kahneman, 1981). Least effort is an important prin-
ciple in the study of crime journeys.

When multiple destinations of equal desirability are available, the least-

effort principle suggests the closest one will be chosen. The determination

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of “closest,” however, can be a problematic assessment. Isotropic surfaces,
spaces exhibiting equal physical properties in all directions, are rarely found
within the human geographical experience. Instead, individuals are con-
fronted with anisotropic surfaces where movement is easier in some direc-
tions or along certain routes, and harder along others. People travel through
networks of roads and highways by “wheel distance” (Rhodes & Conly, 1981)
rather than by Euclidean distance.

Other factors can be just as important as physical space. Macrolevel travel

choices are influenced by time and money expenditures — distance is not as
important as connections, time, and costs to an air traveller. Income and
socioeconomic status thus have important influences on spatial behaviour,
as a shortage of financial resources constrains choices and determines which
options are seen as viable.

Microlevel movement within cities is similarly affected; urban areas are

primarily anisotropic, often conforming to some variation of a grid or Man-
hattan layout

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 (Lowe & Moryadas, 1975), with dissimilar traffic flows along

different routes. As it is not just a question of minimizing distance, but of
reducing time, effort, and costs, the layout of a city, an offender’s mode of
transportation, and any significant mental or physical barriers must also be
considered in the spatial analysis of crime patterns.

The subjective psychological perception of distance is just as critical as

the objective physical space involved. An individual’s perception of distance
is influenced by several factors, including (Stea, 1969):

1. Relative attractiveness of origins and destinations;
2. Number and types of barriers separating points;
3. Familiarity with routes;
4. Actual physical distance; and
5. Attractiveness of routes.

While the nearness principle appears to be a simple one, its actual imple-

mentation is complicated, requiring an awareness of both objective (physical)
and subjective (cognitive) factors. In understanding human movement it is
just as important to take into account mental or cognitive maps and their
creation as it is to consider physical maps.

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Studies of movement within different city structures require different metrics. The grid

(Manhattan) pattern describes most North American cities, but crow-flight measures are
more useful for studies of British cities. Both Manhattan and crow-flight distances are
specific forms of the more general Minkowski metric (Waters, 1995b). An individual’s
mental map and internal representation of the spatial environment, however, may influence
movement more than the external world does.

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6.2 Mental Maps

Mental maps

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 are cognitive images of familiar areas such as neighbourhoods

or cities, formed from a distillation of the particular transactions a person
has with his or her surroundings. Unlike hummingbirds and other animals
that retain detailed images of their spatial experiences, humans generalize
this knowledge within their memories. Mental maps have an influence on
crime site selection because a target cannot be victimized unless an offender
is first aware of it.

A mental map is a representation of the spatial form of the phenomenal
environment which an individual carries in his or her mind. The represen-
tation is of the individual’s subjective image of place (not a conventional
map) and not only includes knowledge of features and spatial relationships
but also reflects the individual’s preferences for and attitudes towards places
.... The product of this process, at any point in time, is a mental or cognitive
map and can be shown cartographically as a perception surface. (Goodall,
1987, p. 299)

These images are the result of the reception, coding, storage, recall,

decoding, and interpretation of information; cognitive maps also involve
nonspatial dimensions such as colour, sound, feeling, sentiment, and sym-
bolization (Brantingham & Brantingham, 1984; Clark, 1990).

Geographic information is an important determinant of movement and

therefore of one’s social, employment, educational, and economic position
(Gould, 1975); but this information is incomplete, and ignorance barriers
based on linguistic, political, natural, religious, and cultural differences may
form (Brantingham & Brantingham, 1984; Gould & White, 1986). Spatial
interaction is thus influenced by an individual’s location, both geographic
and social, and the knowledge and perception held of viable movement
options.

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While cognitive images vary in relation to a person’s biography, social

class, location, and environment, most people’s mental maps have much in
common. This results from the fact that humans perceive things in like
fashion. Lynch (1960) states image composition is based on five elements:

1. Paths — routes of travel that tend to dominate most people’s images

of cities (e.g., highways, railways);

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Individuals spatially interact with many different areas and therefore require several

maps, resulting in mental atlases (Lowe & Moryadas, 1975).

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See Rengert and Wasilchick (1985) for a discussion of the influence of geographic infor-

mation on burglary target selection.

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2. Edges — boundaries of lines that help to organize cognitive maps

(e.g., rivers, railroads);

3. Districts — subareas with recognizable unifying characteristics, pos-

sessing well-established cores but fuzzy borders (e.g., financial dis-
tricts, skid roads);

4. Nodes — intense foci of activity (e.g., major intersections, railroad

stations, corner stores); and

5. Landmarks — symbols used for orientation but which typically are

not physically entered (e.g., signs, tall buildings, trees).

6.3 Awareness and Activity Spaces

Mental maps are developed from individuals’ experiences within their aware-
ness space. An awareness space is defined as:

all the locations about which a person has knowledge above a minimum
level even without visiting some of them ... Awareness space includes activity
space (the area within which most of a person’s activities are carried out,
within which the individual comes most frequently into contact with others
and with the features of the environment), and its area enlarges as new
locations are discovered and/or new information is gathered. (Clark, 1990,
pp. 24–25)

An activity space

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 contains those areas that comprise a person’s habitual

geography, made up of routinely (daily or weekly) visited places and their
connecting routes (Jakle, Brunn, & Roseman, 1976). Activity space plays a
central role in the Brantingham and Brantingham model of crime site selec-
tion, and therefore is an integral part of the theory underlying geographic
profiling. “Where we go depends upon what we know ... What we know
depends on where we go” (Canter, 1994, p. 111).

Mental maps provide the outer limits of potential action space, which may
be defined as the area containing the majority of destinations of a particular
individual. It is a subspace within the mental map and frequently tends to
be discontinuous in the sense that stretches of unknown, possibly undesir-
able, territory lie between preferred areas. The configuration of action space
is frequently linear, especially in automobile-oriented societies. Moreover,
movement patterns defining action space may have well-marked directional
biases from an individual’s home base, so elongation in one direction is
offset by attenuation in other directions. (Lowe & Moryadas, 1975, p. 139)

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Some writers use the term action space for both activity space and awareness space.