Geoscience Reference
In-Depth Information
TABLE 9.2 (continued)
Study of Schelling Model Dynamics according to Benenson and Hatna (2011) Including
the Model Settings and Parameters
Minority-Majority
: Satisficer agents; different numbers of dark and light greys; high density of occupied cells; low rate
of random migration.
Dynamics
: For the F values within a certain interval that depends on the ratio of dark and light greys, the pattern is
neither random nor segregated, but mixed. It consists of the segregated part occupied by the majority and an integrated
part randomly occupied by members of two groups.
Parameters
Persistent Patterns
β = 0.25
d = 0.02
R = 5
m = 0.01
F
B
= F
G
= F F = 5/48 F = 7/48 F = 11/48 F = 13/48
Asymmetric Demand
: Satisficer agents; different numbers of dark and light greys; high density of occupied cells; low
rate of random migration.
Different values of F for the dark greys (F
B
) and for the light greys (F
G
), F
B
≠ F
G
.
Dynamics
: For values of F
B
and F
G
within certain intervals that depend on the ratio of dark and light greys and the
values of F
B
and F
G
, mixed patterns of the kind that are different from those emerging in the minority-majority case
are emerging here.
Parameters
Persistent Patterns
β = 0.3
d = 0.02
R = 5
m = 0.02
F
G
= 0
F
B
F
B
= 17/48
F
B
= 19/48
F
B
= 23/48
F
B
= 27/48
F
B
= 29/48
9.3.6 l
eSSonS
froM
the
S
chelling
M
odel
The Schelling model deals with popular dynamic phenomena and is undoubtedly the most studied
theoretical AB model in geography. What can we learn from this forerunner? The major lesson is
clearly in the importance of model details,
and the examples in Section 9.3.4 demonstrate this with
regard to the ratio of the group numbers and the formalisation of the behaviour of the agents as
satisfiers versus maximisers. For the AB modeller, this conclusion is quite ambiguous. On the one
hand, it confirms the adequateness of the approach, that is, the variety of abstractions of residential
behaviour is essentially meaningful, and different views result in different outcomes. On the other
hand, it provokes essential scepticism - is it possible to specify these details based on common sense
or is never-ending experimental and/or field research required?
Following the sceptical line, it is hardly possible to decide whether real-world householders are
satisficers or maximisers and whether they tend to improve their residential conditions step by step
or whether they would delay moving until they find a residence that perfectly fits their needs for the
next decade at least. Different householders can behave differently and the same person can employ
different tactics in different situations.
