Self testRefer to the time series data in Exercise $1.$ Using the average of all the historical data as a forecast for the next period, compute the following measures of forecast accuracy:

Mean absolute error

Answer

The following table shows the calculations for parts $($a$),($b$),$ and $($c$).$

Mean squared error

Answer

The following table shows the calculations for parts $($a$),($b$),$ and $($c$).$

Mean absolute percentage error

Answer

The following table shows the calculations for parts $($a$),($b$),$ and $($c$).$

What is the forecast for week $7?$

Answer