Alpha $=0\mathrm{.}3$

Quarter Demand $($in $1000$s$)$ Exponential Smoothing $(0\mathrm{.}3)$ Absolute Deviation

$142$

$258$

$371$

$456$

$1$

$1.(20$ pts$)$ Forecastdemand using Exponential Smoothing.

$2.(20$ pts$)$ Compute the mean absolute deviation $($MAD$).$ Intermediate steps shown in colume D$.$

MAD

$3.(5$ pts$)$ Compared to the exponential smmothing method, do you think a forecasting method that corrects for trend and seasonality can provide better forecast? Why?

Hint. Please check whether the demand history shows trend or seasonality.