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where
) denotes characteristic, equaling to the ratio of the number of bits
which are not equal to # with the number of all bits in condition part;
R
(
C
S
(
C t
)
denotes the intensity of C at moment
t
; c is a constant small than 1, such as 1/8 or
1/16.
Victorious bidders put message in message table, and at the same time their
intensities reduces bidding scale. Take classifier
C
for example:
S(
C t
+1) =
S
(
C t
) -
B
(
C t
)
(13.15)
while classifier {
'} for matching message sent by victorious bidders increase
their intensities, their values are equal to bidding scale:
C
S
(C' t
+1) =
S
(
C' t
) + aBid(
C t
)
(13.16)
where a =1/(the cardinality of { C '}).
Fig. 13.7 presents two purposes of bid: supporting service and shift of bid by
message flow. In addition, bid is used to modify provider's intensity.
% & W
&
% & W
9& W %& W%& W%& W
&
% & W
&
Fig. 13.7. Intensity of classifier is modified by bid
If the system can learn effectively and work steadily, and related results are
acceptable, then the decentralization of rule intensity can be reduced. If the
decentralization can not be controlled, system may adopt the rules with high
intensity, such leading to loss of useful rules with low intensity. For changes of
bidding competition and that of mechanism of message generation, some of them
require “parasitic” rules to be controlled, while some require finite message table
be utilized effectively.
13.6 Genetic Algorithm
Holland had abstractly analyzed adaptive process of natural system, and had
designed artificial system having adaptive features of natural system. In this kind
of artificial system, an adaptive process is described as a search process in
changing structural space. He pointed out: Many complex structures can be
coded in the simple form of bit strings; These bit strings can gradually
improved by some simple transforms, so that they transform toward good
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