The analytics department is researching the past five years of their company’s sales to better prepare for the future. The company has experienced a variation in sales for no known reason and wants to ...

The analytics department is researching the past five years of their company’s sales to better prepare for the future. The company has experienced a variation in sales for no known reason and wants to develop a forecast using the exponential smoothing method. Using data from the previous 20 days, the following summary table was calculated. What is the MSE?

Day	Sales	At	?t	et = y1 –	e2	|e|
1	70
2	69	69.7	70	-1	1	1
3	67	68.89	69.7	-2.7	7.29	2.7
...	...	...	...	...	...	...
20	61	63.03	63.03	-2.898	8.39682	2.8977
Total					206.064	51.211

Solution: