An analyst must decide between two different forecasting techniques for weekly sales of roller blades: a linear trend equation and the

naive approach. The linear trend equation is $F_t=127+1\mathrm{.}9t,$ and it was developed using data from periods $1$ through $10.$

Based on data for periods $11$ through $20$ as shown in the table, develop a linear trend forecast for periods $11$ through $20,$ and a naive

forecast for periods $11$ through $20,$ then calculate MAD for each method. Which forecast has the greater accuracy, according to your

MAD?

$($Round your intermediate calculations and final answers to $2$ decimal places.$)$

Click here for the Excel Data File

MAD for naive forecast:

MAD for linear trend forecast:

A forecast with less average absolute error is provided by the

Naive method

Linear trend

method.