Question 1 |

The demand and forecast of an item for five months are given in the table.

\begin{array}{|c|c|c|}\hline \textbf{Month} & \textbf{Demand} & \textbf{Forecast} \\ \hline \text{April} & \text{225} & \text{200} \\ \hline \text{May} & \text{220} & \text{240}\\ \hline \text{June} & \text{285} & \text{300} \\ \hline \text{July} & \text{290} & \text{270} \\ \hline \text{August} & \text{250} & \text{230} \\ \hline \end{array}

The Mean Absolute Percent Error (MAPE) in the forecast is _______% (round off to two decimal places)

\begin{array}{|c|c|c|}\hline \textbf{Month} & \textbf{Demand} & \textbf{Forecast} \\ \hline \text{April} & \text{225} & \text{200} \\ \hline \text{May} & \text{220} & \text{240}\\ \hline \text{June} & \text{285} & \text{300} \\ \hline \text{July} & \text{290} & \text{270} \\ \hline \text{August} & \text{250} & \text{230} \\ \hline \end{array}

The Mean Absolute Percent Error (MAPE) in the forecast is _______% (round off to two decimal places)

4.45 | |

12.25 | |

18.42 | |

8.08 |

Question 1 Explanation:

\begin{array}{|c|c|c|c|c|} \hline \text { March } & \mathrm{Di} & \mathrm{Fi} & \mathrm{ei} & \left|\frac{\mathrm{ei}}{\mathrm{Di}} \times 100\right| \\ \hline \text { April } & 225 & 200 & 25 & 11.11 \% \\ \hline \text { May } & 220 & 240 & -20 & 9.09 \% \\ \hline \text { June } & 285 & 300 & -15 & 5.26 \% \\ \hline \text { July } & 290 & 270 & 20 & 6.896 \% \\ \hline \text { August } & 250 & 230 & 20 & 8.0 \% \\ \hline & & & & \sum \frac{e i}{D i} \times 100 \mid=40.356 \\ \hline \end{array}

\text{MAPE}=\frac{\sum\left|\frac{e i}{D i} \times 100\right|}{n}=8.0712 \%

\text{MAPE}=\frac{\sum\left|\frac{e i}{D i} \times 100\right|}{n}=8.0712 \%

Question 2 |

Daily production capacity of a bearing manufacturing company is 30000 bearings. The daily demand of the bearing is 15000. The holding cost per year of keeping a bearing in the inventory is Rs. 20. The setup cost for the production of a batch is Rs. 1800. Assuming 300 working days in a year, the economic batch quantity in number of bearings is ______ (in integer).

36254 | |

20145 | |

40250 | |

42145 |

Question 2 Explanation:

\begin{aligned} Q^{\star} &=\sqrt{\frac{2 D \times C_{0}}{C_{h}} \times \frac{P}{P-d}} \\ &=\sqrt{\frac{2 \times 15000 \times 300 \times 1800}{20} \times\left(\frac{30000}{30000-15000}\right)} \\ &=40249.2 \simeq 40250 \text { units } \end{aligned}

Question 3 |

The forecast for the monthly demand of a product is given in the table below.

The forecast is made by using the exponential smoothing method. The exponential smoothing coefficient used in forecasting the demand is

The forecast is made by using the exponential smoothing method. The exponential smoothing coefficient used in forecasting the demand is

0.1 | |

0.4 | |

0.5 | |

1 |

Question 3 Explanation:

\begin{aligned} F_{t}&=F_{t-1}+\alpha\left(D_{t-1}-F_{t-1}\right)\\ \text{For 2nd month }F_{t}&=31.8, \text{ for }1^{\text {st }} \text{month}\\ F_{t-1} &=32 \text { and } D_{t-1}=30 \\ 31.8 &=32+\alpha(30-32) \\ 2 \alpha &=32-31.8 \\ \alpha &=0.1 \end{aligned}

Question 4 |

The table presents the demand of a product. By simple three-months moving average method, the demand-forecast of the product for the month of September is

490 | |

510 | |

530 | |

536.67 |

Question 4 Explanation:

3 month moving average method :

\begin{aligned} \mathrm{F}_{\mathrm{sep}} &=\frac{\mathrm{D}_{\mathrm{Aug}}+\mathrm{D}_{\mathrm{July}}+\mathrm{D}_{\text {June }}}{3} \\ &=\frac{560+475+495}{3}=510 \end{aligned}

\begin{aligned} \mathrm{F}_{\mathrm{sep}} &=\frac{\mathrm{D}_{\mathrm{Aug}}+\mathrm{D}_{\mathrm{July}}+\mathrm{D}_{\text {June }}}{3} \\ &=\frac{560+475+495}{3}=510 \end{aligned}

Question 5 |

The time series forecasting method that gives equal weightage to each of the m most recent observations is

Moving average method | |

Exponential smoothing with linear trend | |

Triple Exponential smoothing | |

Kalman Filter |

Question 5 Explanation:

It gives equal weightage to all data points.

Question 6 |

The demand for a two-wheeler was 900 units and 1030 units in April 2015 and May 2015, respectively. The forecast for the month of April 2015 was 850 units. Considering a smoothing constant of 0.6, the forecast for the month of June 2015 is

850 units | |

927 units | |

965 units | |

970 units |

Question 6 Explanation:

\begin{aligned} F_{May} &=F_{April} +0.6(D_{April}-F_{April})\\ &=580+0.6(900-850) \\ &= 850+30\\ &= 880\; unit\\ F_{June} &=F_{May} +0.6(D_{May}-F_{May})\\ &=880+0.6(1030-880) \\ &= 880+90\\ &= 970\; unit\\ \end{aligned}

Question 7 |

Sales data of a product is given in the following table:

Regarding forecast for the month of June, which one of the following statements is TRUE?

Regarding forecast for the month of June, which one of the following statements is TRUE?

Moving average will forecast a higher value compared to regression. | |

Higher the value of order N, the greater will be the forecast value by moving average. | |

Exponential smoothing will forecast a higher value compared to regression. | |

Regression will forecast a higher value compared to moving average. |

Question 7 Explanation:

As regression follow a pattern

\text{(forecast)}_{\text {June }} according to regression \gt 25

but according to moving average,

T_{\text {June }} \lt 25

\text{(forecast)}_{\text {June }} according to regression \gt 25

but according to moving average,

T_{\text {June }} \lt 25

Question 8 |

For a canteen, the actual demand for disposable cups was 500 units in January and 600 units in February. The forecast for the month of January was 400 units. The forecast for the month of March considering smoothing coefficient as 0.75 is ________

569 | |

986 | |

451 | |

258 |

Question 8 Explanation:

\begin{aligned} F_{\mathrm{Feb}} &=F_{\mathrm{Jan}}+\alpha\left[D_{\mathrm{Jan}}-F_{\mathrm{Jan}}\right] \\ &=400+0.75[500-400] \\ &=475 \\ F_{\mathrm{March}} &=F_{\mathrm{Feb}}+\alpha\left[D_{\mathrm{Feb}}-F_{\mathrm{Feb}}\right] \\ &=475+0.75[600-475] \\ &=568.75 \approx 569 \end{aligned}

Question 9 |

The actual sales of a product in different months of a particular year are given below:

The forecast of the sales, using the 4-month moving average method, for the month of February is _______

The forecast of the sales, using the 4-month moving average method, for the month of February is _______

156 | |

240 | |

654 | |

852 |

Question 9 Explanation:

F=\frac{280+250+190+240}{4}=240

Question 10 |

In exponential smoothening method, which one of the following is true?

0\leq \alpha \leq 1 and high value of \alpha is used for stable demand | |

0\leq \alpha \leq 1 and high value of \alpha is used for unstable demand | |

\alpha \geq 1 and high value of \alpha is used for stable demand | |

\alpha \leq 0 and high value of \alpha is used for unstable demand |

Question 10 Explanation:

High value of \alpha shows more weightage is given to immediate forecast. Less value of \alpha shows less weightage is given to immediate forecast or almost equal weightage is given. So high value of \alpha is chosen when nature of demand is not reliable or unstable.

There are 10 questions to complete.