Selecting smoothing constant is a decision when applying exponential smoothing method. When you have previous data, one approach to making this approach decision is to apply the method retrospectively to these data with different values of smoothing constant and then choose the value of smoothing constant that gives the smallest MAD. Use this approach for choosing smoothing constant with each of the following data, which represent monthly sales. In each case, use an initial estimate of 50 and compare with the following smoothing constants of 0.1, 0.2, 0.3, 0.4, and 0.5

a. 51, 48, 52, 49, 53, 49, 48, 51, 50, 49

b. 52, 50, 53, 51, 52, 48, 52, 53, 49, 52

c. 50, 52, 51, 55, 53, 56, 52, 55, 54, 53

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