Exercise on Forecasting

Exercise Question 1

John is responsible for coming up with a forecast of the number of visitors to Metro Zoo. He has gathered the following data on the number of visitors over the last seven weeks:

Week	Week 1	Week 2	Week 3	Week 4	Week 5	Week 6	Week 7
Visitors	620	730	880	700	830	1,020	900

Based on the data above, what is Johns forecast of the number of visitors for week 8 using each of the following methods?

1. Nave forecast.

2. A three-period moving average

3. A five-week weighted moving average using a weight of 0.3 for t-1 (i.e., one period before), 0.25 for t-2 (i.e., two periods before), 0.2 for t-3 (i.e., three periods before), 0.15 for t-4 (i.e., four periods before) and 0.1 for t-5 (i.e., five periods before).

4. An Exponential Smoothing method, assuming that the forecast for week 5 was 900, using a value of 0.3 for .

Exercise Question 2

Based on the data shown in the table below,

Calculate the forecasting performance measures using the following methods. [Show all your calculations and put each of your final answers in the box in front of each method].

Period	A	F
1	54	58
2	47	56
3	50	52
4	42	51

Mean Absolute Deviation (MAD)=

Mean Squared Error (MSE)=

Mean absolute percent error (MAPE) =