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Artificial Intelligence and Soft Computing: Behavioral ... - Arteimi.info

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where the n-step transition matrix Nn is given by<br />

Nn = I + Q + Q 2 + Q 3 + ……+ Q n - 1 (15.19)<br />

As n approaches infinity,<br />

Lt N n = ( I – Q ) - 1 . (15.20)<br />

n→∝<br />

Consequently, as n approaches infinity,<br />

Lt P n =<br />

n→∝<br />

Goodman has shown [8] that the matrix (I – Q) -1 is guaranteed to exist.<br />

Thus given an initial probability vector π 0, the chain will have a transition to<br />

an absorbing state with probability 1. Further, there exists a non-zero<br />

probability that absorbing state will be the globally optimal state [8].<br />

We now explain: why the chain will finally terminate to an absorbing<br />

state. Since the first ‘a’ columns for the matrix P n , for n →∝, are non-zero <strong>and</strong><br />

the remaining columns are zero, therefore, the chain must have transition to<br />

one of the absorbing states. Further, note that the first ‘a’ columns of the row<br />

vector π n for n →∝ denote the probability of absorption at different states,<br />

<strong>and</strong> the rest of the columns denote that the probability of transition to nonabsorbing<br />

states is zero. Thus probability of transition to absorbing states is<br />

one. Formally,<br />

a<br />

∑ Lt (π n ) i<br />

i=1 n→∝<br />

I 0<br />

(I – Q ) – 1 R 0

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