Question $2$:

$[20]$

A company needs to decide which forecasting method will yield the most accurate forecasting data for them going forward. They are considering either the Exponential Smoothing method, or a Weighted Average method. The following table gives the resulting forecasts of both methods versus the actual sales data.

$\backslash$table$[[,$Forecasts based on:$],[$Period$,$Actual Sales,Exponential Smoothing,Weigted Average$],[1,4455,4455,4453],[2,4489,4455,4453],[3,4501,4479,4471],[4,4606,4494,4490],[5,4689,4572,4556],[6,4777,4654,4633],[7,4862,4740,4718],[8,4432,4825,4804],[9,4009,4550,4600],[10,4756,4171,4260],[11,4822,4580,4517],[12,4638,4749,4695],[13,4899,4671,4678],[14,4814,4830,4802],[15,4814,4830,4803]]$

$|)/(A$

MAPE

Round off all answers to two decimal places.

$2\mathrm{.}1$ Calculate the MAD, MSE and MAPE for each of the forecasting methods above.

$12$

$2\mathrm{.}2$ Motivate what forecasting method would you recommend based on your calculations?

$[4]$

$2\mathrm{.}3$ What value does it hold in calculating the forecasted error data for inventory planners?

$[4]$