Swarm Intelligence

other binary decision, is a function of personal and social factors (Ken-

nedy and Eberhart, 1997):

Px t f x t v t p p

id id id id gd

(() ) (( ),( ), , )== − −111

where

■

P(x

id

(t)=1) is the probability that individual i will choose 1 (of

course the probability of their making the zero choice is 1 − P) for

the bit at the dth site on the bitstring

■

x

id

(t) is the current state of the bitstring site d of individual i

■

t means the current time step, and t − 1 is the previous step

■

v

id

(t − 1)is a measure of the individual’s predisposition or current

probability of deciding 1

■

p

id

is the best state found so far, for example, it is 1 if the individ-

ual’s best success ...