Generating Patterns
Section 2 - Page 2
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A Markov process is a process which moves from state to state
depending (only) on the previous n states. The process is
called
an order n model where n is the number of states
affecting the
choice of next state. The simplest Markov process is a first
order process, where the choice of state is made purely on the
basis of the previous state. Notice this is not the same as a
deterministic system, since we expect the choice to be made
probabalistically, not deterministically.
The figure below shows all possible first order transitions
between the states of the weather example.
Notice that for a first order process with M states, there are
M2 transitions between states since it is possible for
any one
state to follow another. Associated with each transition is a
probability called the state transition probability - this is
the probability of moving from one state to another.
These M2
probabilities may be collected together in an obvious way into a
state transition matrix. Notice that these probabilities do not
vary in time - this is an important (if often unrealistic)
assumption.
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