QUESTION $5(20$ Marks$)$

Using the information provided below, answer the following questions.

INFORMATION

The data in the table below shows the number of Next$-$generation Rangers exported to over $100$ countries through Durban$$s roll$-$on

roll$-$off $($RORO$)$ vehicle terminal during $2022$ and the first quarter of $2023.$

Month Jan$22$

Feb$22$

Mar$22$

Apr$22$

May$22$

Jun$22$

Jul$22$

Aug$22$

Sep$22$

Oct$22$

Nov$22$

Dec$22$

Jan$23$

Feb$23$

Mar$23$

Export,

units $70009000860095001020012000110001250012000126001280013000108001260014000$

A demand planner wants to compare the relative performance of the weighted moving average method against the simple

exponential method in forecasting the volume of export of the next$-$gen Ranger from the Silverton Assembly Plant.

Required:

$5\mathrm{.}1.$ Using the simple exponential smoothing method $($SESM$),$ compute the forecasts for the February $2022$ to March $2023$ period.

Use a smoothing constant of $0\mathrm{.}2$ and assume a forecast of $7000$ units for January $2022.$

$(5$marks$)$

$5\mathrm{.}2.$ Compute the three$-$month weighted moving average $(3$MWMA$)$ forecasts for the April $2022$ to March $2023$ period, using weights

of $0\mathrm{.}2,0\mathrm{.}3,$ and $0,5($oldest data to newest data, respectively$).$

$(5$marks$)$

$5\mathrm{.}3.$ Using the forecasts calculated for the April $2022$ to March $2023$ period, calculate the Mean Absolute Percentage Error $($MAPE$)$

of the simple smoothing method and the MAPE of the three$-$month weighted moving average method.

$(8$marks$)$

$5\mathrm{.}4.$ Which of the two methods should the demand planner use to forecast the volume of export of the next$-$Gen Ranger. Explain

why?

$(2$marks$)$