$1)$ View the video Service Processing at BuyCostumes $(10\mathrm{.}41$ minutes, Ctrl$+$Click on the link$)$; what are your key takeaways $($tie to one or more of the topics discussed in Chapter $3)$ after watching this video. $($viddler$.$com$/$embed$/$a$6$b$7054$c$)$

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Note: As a rough guideline, please try to keep the written submission to one or two paragraphs.

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$2)$ Orkhon Foods makes hand$-$held pies $($among other products$).$ The firm$$s weekly sales of hand$-$held pies over the past seven weeks are given in the table. The firm$$s operations manager, Amarjargal, wants to forecast sales for week $8.$

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Weeks

Sales of hand$-$held pies$(000$s$)$

$1$

$19$

$2$

$18$

$3$

$17$

$4$

$20$

$5$

$18$

$6$

$22$

$7$

$20$

Forecast the week $8$ sales using the following approaches:

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a$)$ Na$$ve approach

b$)5-$month moving average

c$)3-$month weighted moving average using the following weights: $0\mathrm{.}50$ for week $7,0\mathrm{.}30$ for week $6,$ and $0\mathrm{.}20$ for week $5.$

d$)$ Exponential smoothing using a smoothing constant of $0\mathrm{.}30,$ assume a week $2$ forecast of $19(000$s$).$

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Note: You could work out the problem by hand or use excel; in chapter $3,$ section $3\mathrm{.}8$ of the Stevenson text, forecasts based on time$-$series data $($naive methods, techniques for averaging$)$ are covered with examples; chapter $3$ Stevenson lecture power point slides $16$ to $22,25$ to $29($chapter $3$ lecture: $8\mathrm{.}37$ mins to $14\mathrm{.}18$ mins, $17\mathrm{.}50$ mins to $20\mathrm{.}20$ mins$)$ cover forecasts based on time$-$series data $($naive methods, techniques for averaging$)$ with examples.

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$3)$ The demand and forecasts for the accessories of Dornogovi Medical$$s Spectralis ophthalmic diagnostic imaging device for the past four months is given below.

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Sales

Forecast

Error

Abs Error

Error squared

Pct$.$ error

$80$

$60$

$$

$$

$$

$$

$100$

$80$

$$

$$

$$

$$

$105$

$95$

$$

$$

$$

$$

$90$

$75$

$$

$$

$$

$$

$$

$$

$$

Sum $=$

Sum $=$

Sum $=$

$$

$$

$$

n $=$

n $=$

n $=$

$$

$$

$$

MAD $=$

MSE $=$

MAPE $=$

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a$)$ Calculate MAD, MSE, and MAPE.

b$)$ Which would be the better measure $($MAD$/$MSE$/$MAPE$)$ to use, and why?