Question: Consider the data for Problem.
a. Using the data from Years 2 and 3, determine initial values of the intercept, slope, and seasonal factors for Winters's method.
b. Assume that the observed demand for the first quarter of Year 4 was 18. Using
α = .2, β = .15, and γ = .10,
update the estimates of the series, the slope, and the seasonal factors.
c. What are the forecasts made at the end of the first quarter of Year 4 for the remaining three quarters of Year 4?
Problem: A popular brand of tennis shoe has had the following demand history by quarters over a three-year period.