Question

The table below shows the probability distribution of a random variable y Y Y Р(N) -7 0.04 -6 0.32 -5 0.49 -4 0.04 -3 0.1 -2 0.01 What is the expected value of Y? Vrite your answer as a decimal.

Answer 1

The basic expected value formula is the probability of an event multiplied by the number of times the event happens: (P(Y) * n).

From the data given in the question, Each random variable (Y) has a probability (P)

The expected value will e the sum of the products of (P) x (Y)

-7 x 0.04 => -0.28

-6 x 0.32=> -1.92

-5 x 0.49 => -2.45

-4 x 0.04 => -0.16

-3 x 0.1 => -0.3

-2 x 0.01 => -0.02

Total = -0.28 -1.92 -2.45 -0.16 - 0.3 -0.02 = -5.13

Expected value = -5.13