ows integration
ctural models/
patio-temporal
combinatorial
1etic algorithm
jle data to get
e likelihood is
ion results both
ictural models/
EGRATING
RVATIONAL
OLATION
coding)
nsional array is
ure.1). While,
2D space and
oral dimension.
idual
: algorithm is
ial is made to
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ure so that the
ulation is same.
d 3*3*3 pixels
population to
dual's Fitness
Rules of Class
odels/rules can
/ can determine
r/transition of
variable data,
isically defined
lass to another.
One of the simplest example is a Markov chain, where
transitional probability is determined only by the previous
class. In addition the probability also can be affected by
combination of classes in the neighborhood. In this study,
we assume a model at which transitional probability is
determined by the combination of classes in the
neighborhood. And landcover data with five classes is used
as test data.
In an example model which we used in an
experiment, spatial and temporal relations affect the
transitional probability in three ways as shown in the
Figure.2. The first one can be called "spatial continuity",
based on the assumption that the same class data tends to
continue in spatial dimension. Second one is called temporal
continuity. This is an extension of spatial continuity to
temporal domain. The third aspect is expansion-contraction
relations based on the assumption that some class data has
high possibility to expand its area at next time-slice, while
others tend to contract. The temporal change in the pixel
with un-contractible class type will be determined by the
pixels class itself. And the temporal landuse change in the
pixel with contractible type will be determined by class of
the pixel and classes of its expansible neighborhood.
TEMPORAL;
CONTINUITY !
Figure.2 3D Spatial- Temporal Relation of
Pixel-based Class Variable Data
3.3.2 Definition and Computation of Fitness of an
Individual
Fitness of an individual is defined by the combination
of behavioral fitness and observational fitness. Behavioral
fitness is defined as combined probability of change events
of nominal variables under the condition that these changes
follow a given probabilistic behavioral model or rule.
Observational fitness can be defined as combined probability
that the observational nominal values occur under
probabilistic functions of observational errors/uncertainties.
Observational probability can be determined by accuracy,
resolution and frequency of observation. By multiplying
behavioral fitness and observational fitness, overall fitness
can be computed. Behavioral/structural models and
observational data can be integrated by optimizing the
overall fitness.
805
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B3. Vienna 1996
1)Behavioral Fitness: As showing in Figure.2, let
PAC Cp pu) 85 the probability of changes from
landuse class C,, to landuse class C, considering the
expansion-contraction effect of its neighbourhood, and
Esc (C, - C, ) as the probability of spatial continuity. If we
assume that P_{(C,.C.Y% and PB IC ~C ) are
independent, we can compute behavioral fitness of each
individual according to following formula:
Np N,
FITNESS 7 [1 4, Il B Cho Corn?!
(behavioralfitness) P1 =]
Np N;
= i { H Pr (C... e ECC, e e Cor Ci) j
where N, : is the pixel number in 2D space,
N, : is the temporal slice number,
C, , : is the landuse class of the cell on the
Pth pixel at the T time slice;
For the class change probability with spatial
continuity, E (Ca 7 C,,), we set values according to
following five neighboring pixel's statues along the spatial
dimension, which form a set of behavioral rules: 1)If or
not classes in all neighbouring pixels are equal; 2) If or not
classes in 4 neighbouring pixels are equal; 3) If or not classes
in 3 neighbouring pixels are equal; 4) If or not classes in 2
neighbouring pixels are equal; 5) If all classes in 5 pixels
are unequal.
To calculate the probability of class changes under
the temporal continuity/expansion-contradiction effect,
B, (C,,. C.) , three possible changing patterns of landuse
classes in spatial-temporal distribution are picked up and
listed in the Figure.3. They will be determined based on
the probability integrating class changes in Markov chain,
P, (C, C.) , and expansion speed of class-types into
neighboring pixels. Their behavioral rules can be reckoned
from tables similar to Table.1.
2) Observational Fitness: Observational fitness can
be computed with the following formula. Observational
probability can be determined mainly by the accuracy of
ESO f Cu Cu Ca = Ce: |; Others
= + = > ~
une dr (c care, cp Cy Pi €)
Yes | Yes :
(Oc. Ni. 3 0 0 Invasion 0
Yes No d ;
( oc, | (1-00, | Invasion 0 Invasion 0
No | Yes 4 xv
ao do.) 0 Invasion | Invasion 0
No No | Markov | Markov | Markov | Markov
(1-0) (1-2) Chain Chain Chain Chain
Notice: 1> Supposed C,;, and C,, are expansible (il, i2 21 — 4);
2» 0c, and Oc, are defined as expansion speed of C, , and C,,;
Table.1 Behaviors of Class Changing in Case3