(Sample Mean) The sample mean is the BEST estimate of weekly demand ___.

of 40 always

equally likely between 30 and 50

equally likely between 20 and 60

equally likely between 10 and 70

equally likely between 0 and 80

(Sample Statistics) Given a sample of {1, 3, 5}, the sample standard deviation is ___.

ID: A

A. 1 B. 1.33 C. 1.5 D. 1.67

E. 2 F. 2.33 G. 2.5 H. 2.67

(Four Retailers) Ten-day demands were collected from four retailers (W, X, Y, Z) in a supply chain. Day W X Y Z

1 56 47 27 16 2 21 38 70 0 3 40 30 28 12 4 71 50 23 20 5 25 32 56 4 6 45 48 27 14 7 28 36 40 8 8 27 38 45 6 9 64 45 23 18

10 23 36 61 2

Use the Excel data (Four Retailers Data) to answer the questions below. 3. (Four Retailers) Use AVERAGE in Excel to find the means of four retailers' (W, X, Y, Z) demands.

A. 39,39,39,10 B. 39,39,40,11 C. 39,40,40,12 D. 40,40,40,13

E. 40,40,40,10 F. 40,40,41,11 G. 40,41,41,12 H. 41,41,41,13

4. (Four Retailers) Use STDEV in Excel to find the standard deviations of four retailer's (W, X, Y, Z) demands.

17.16, 6.89, 18.18, 6.91 E.

18.18, 6.91, 17.16, 6.89 F.

17.26, 6.99, 18.28, 7.01 G.

18.28, 7.01, 17.26, 6.99 H.

17.36, 7.09, 18.38, 7.11 18.38, 7.11, 17.36, 7.09 17.46, 7.19, 18.48, 7.21 18.48, 7.21, 17.46, 7.19

1

Name: ________________________ ID: A

5. (Four Retailers) Find the coefficients of variation (CV) of four retailers' (W, X, Y, Z) demands.

0.33, 0.6, 0.36, 0.08 E.

0.36, 0.08, 0.33, 0.6 F.

0.43, 0.7, 0.46, 0.18 G.

0.46, 0.18, 0.43, 0.7 H.

0.53, 0.8, 0.56, 0.28 0.56, 0.28, 0.53, 0.8 0.63, 0.9, 0.66, 0.38 0.66, 0.38, 0.63, 0.9

(Four Retailers) Branch ___ has the largest variability in demands. (Hint: Would you use standard deviation or CV?) A. W B. X

C. Y D. Z

(Four Retailers) The supply chain manager plans to merge retailer Z with one of the other three retailers

(W, X, Y). Find the CVs of three pairs' (W+Z, X+Z, Y+Z) aggregate demands.

0.5, 0.21, 0.26

0.5, 0.26, 0.21

0.5, 0.31, 0.36

0.5, 0.36, 0.31

E. 0.21, 0.26, 0.4 F. 0.26, 0.21, 0.4 G. 0.31, 0.36, 0.4 H. 0.36, 0.31, 0.4

(Four Retailers) When merged with retailer Z, retailer ___ reduces variability in aggregate demands the most.

A. W B. X C. Y

(Four Retailers) Use CORREL in Excel to find the correlations of three pairs' (W+Z, X+Z, Y+Z) aggregate demands.

-0.86, 0.6, 0.87

-0.86, 0.87, 0.6

-0.96, 0.7, 0.97

-0.96, 0.97, 0.7

E. 0.6, 0.87, -0.86 F. 0.87, 0.6, -0.86 G. 0.7, 0.97, -0.96 H. 0.97, 0.7, -0.96

10. (Four Retailers) The variability in aggregate demands is ___.

lower for a smaller correlation.

lower for a larger correlation.

not dependent on correlation.