PROBABILITY THEORY:EXPECTATION

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EXPECTATION

Although knowledge of the probability distribution of a random variable enables one to make all sorts of probability statements, a single value that may characterize the random variable and its probability distribution is often desirable. Such a quantity is the expected value of the random variable. One may speak of the expected value of the demand for a product or the expected value of the time of the first customer arrival. In the experiment where the arrival time of the first customer on two successive days was measured, the expected value of the average arrival time of the first customers on two successive days may be of interest.

Formally, the expected value of a random variable X is denoted by E(X) and is given by

INTRODUCTION TO OPERATIONS RESEARCH-0570

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