When calculating U$,$ include in the sum any time period

ME: for which you have a forecast $($in other words, in this

MSE: case, t goes from $2$ to $22).$

MAPE:

U: Make sure when you are taking the average for any of these error measures, that you

you only divide by the number of periods for which you have a forecast. In other words,

in this case, you should only be dividing by $21.$

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$75$

$125$

$175$

$225$

Time

Demand

Demand Forecast