The Markov approach is a concept for predicting stochastic processes. It models a sequence in which the probability of the following (n+1) event depends only on the state of the previous (n) event. Therefore, it is also called a ‘memoryless’ process.
Before performing calculations, let’s familiarise ourselves with the concept and notations. Suppose there are two states: state A and state B. The process is expected to stay in the same stage for 20% of the time and can move to stage B in the remaining 80%. On the other hand, stage B has a 30% chance of staying and a 70% chance of moving to stage A. The following diagram depicts the process.
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For example, imagine three shops in town—A, B, and C—that attract 200, 120, and 180 customers, respectively, this week. The following possibilities are expected for next week.
Shop A:
80% of the customers stay loyal
10% can move shop B
10% can move shop C
Shop B:
70% of the customers stay loyal
20% can move shop A
10% can move shop C
Shop C:
60% of the customers stay loyal
10% can move shop A
30% can move shop B
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The question is, what is the expected number of customers in shops A, B, and C in the following week?