7/24/2019 ''Quiz 9 - T04 - Solutions

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Quiz 9

ENGG 319 T04

Tuesday 24nd

November 2015

Students

Name:

Students

ID:

The correct choice for each question is the closest number to the correct answer.

1. DiamEnd is a small company processing diamond stones using proprietary equipment to increase the clarity

of the stones. The clarity of each stone is measured before and after processing to determine the % increase

in clarity. The following is a scatter plot of the data and calculated values from the sample data:

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Estimate !1for the linear regression curve.

(a) 2.5 (b) 6.2 (c) 10 (d) 15 (e) 35

SOLUTION

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Answer: (a)

2. An experiment is run to determine the relationship between temperature (X in units of degrees Celsius) anddissolved oxygen (Y in units of mg/L) in a new industrial process. The regression coefficients of linear

regression model of the sample data were estimated to be bo = 14.393 and b1 = -0.2214. Predict thedissolved oxygen content in a system at 22

oC (assume that the model is appropriate to use for this value of

X).

(a) 1.2 (b) 2.5 (c) 8.8 (d) 9.5 (e) 15

SOLUTION

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Answer: (d)

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7/24/2019 ''Quiz 9 - T04 - Solutions

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3. Calculate the sum of squares of the errors for the following dataset:

(a) 2.3 (b) 4.3 (c) 5.5 (d) 20 (e) 63

SOLUTION

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Answer: (b)

Measured X Measured Y Predicted Y Residuals

2 22 21.8 0.2

4 23 24.3 -1.3

6 28 26.8 1.2

8 30 29.3 0.7

10 31 31.8 -0.8