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The manager of a seafood restaurant was asked to establish a pricing policy on l

ID: 3203670 • Letter: T

Question

The manager of a seafood restaurant was asked to establish a pricing policy on lobster dinners. The manager intends to use the pricing $/LB to predict the lobster sales on each day. The pertinent historical data are collected as shown in the table. Anaswer the following questions.

Day

Lobster Sold/day

Price ($/lb.)

1

182

6.8

2

156

6.1

3

189

5.6

4

179

7.0

5

170

7.5

6

163

6.5

7

162

7.2


a) x = independent variable. According to this problem, the x =  

b) r is the coeefficient of correlation. Use the r equation to compute the value of the denominator part of the equation. The value for the r denominator =  (in 4 decimal places)

c) According to this problem, the correlation of coefficient, r, between the two most pertinent variables is =  (in 4 decimal places).

d) According to the instructor's lecture, the correlation strength between any two variables can be described as strong, weak, or no correlation. The correlation strength for this problem can be described as  correlation.

e) According to the instructor's lecture, the correlation direction between any two variables can be described as direct or indirect relationship. The correlation direction for this problem can be described as  relationship.

f) Regardless, you were told to use the Associative Forecasting method to predict the expected lobster sale. If the lobster price = $8.58, the expected #s of lobster sold =  (round to the next whole #).

Day

Lobster Sold/day

Price ($/lb.)

1

182

6.8

2

156

6.1

3

189

5.6

4

179

7.0

5

170

7.5

6

163

6.5

7

162

7.2

Explanation / Answer

a)       According to the problem, the sum of X

= ( 182 + 156 + 189 + 179 + 170 + 163 + 162 ) = 1201

b)         

Day

Lobster sold/day, X

Price ($/lb), Y

            X.Y

            X^2

       Y^2

1

182

6.8

1237.6

33124

46.24

2

156

6.1

951.6

24336

37.21

3

189

5.6

1058.4

35721

31.36

4

179

7

1253

32041

49

5

170

7.5

1275

28900

56.25

6

163

6.5

1059.5

26569

42.25

7

162

7.2

1166.4

26244

51.84

Sum =

1201

46.7

8001.5

206935

314.15

We need to find out the value of the denominator of the formula for r as presented in #c

Therefore value of the denominator

= Square root( ( 7 x 206935 – 1201 x 1201) x ( 7 x 314.15 – 46.7 x 46.7))

= Square root (( 1448545 – 1442401) x ( 2199.04   – 2180.89))

= Square root ( 6144 x 18.16 ) = 334.082

c)    The correlation coefficient between lobster sold ( X) and Price (Y) is

= (r) =[ nxy – (x)(y) i.e. NUMERATOR / Sqrt([nx2 – (x)2][ny2 – (y)2])] .i.e. DENOMINATOR

r: The correlation coefficient is denoted by the letter r.

n: Number of values. 7 in this case

x: This is the first data variable.

y: This is the second data variable.

: The Sigma symbol (Greek) tells us to calculate the “sum of” whatever is tagged next to it.

The value of r   = (-) 0.22812

d)Answer: Weak Correlation (since value is far below from 1 and > 0.1)

e)Correlation direction: Indirect relationship (because of negative correlation, one will move in the direction opposite to where other one is moving)

Day

Lobster sold/day, X

Price ($/lb), Y

            X.Y

            X^2

       Y^2

1

182

6.8

1237.6

33124

46.24

2

156

6.1

951.6

24336

37.21

3

189

5.6

1058.4

35721

31.36

4

179

7

1253

32041

49

5

170

7.5

1275

28900

56.25

6

163

6.5

1059.5

26569

42.25

7

162

7.2

1166.4

26244

51.84

Sum =

1201

46.7

8001.5

206935

314.15