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# Multiple regression analayis

Please see the attached 2 problems. Please provide a step by step solution and also use Excel to arrive at the answers. Thank you.

Problem 1: The US Government has asked for your assistance in determining the acceptability of structural bolts provided by a supplier. The bolts must be 1.84 centimeters in diameter. You select 12 random bolts from the pile and measure them getting the following results:

1.81
1.85
1.84
1.89
1.82
1.86
1.86
1.87
1.88
1.83
1.85
1.85
a) The government is asking that your results be accurate to 99%. (this is the same as &#945;=0.01) Based on your sample (assuming the bolt sizes are normally distributed) can you approve this supplier to make the bolts required? Show all your work.

b) If the standards were lowered to 95% accurate, would you approve the supplier to make the bolts? Show your work.

Problem 2: Since you have done such a great job on your first government project, they again have asked for your assistance in predicting how many oil contractors will bid for oil leases on government land. Based on a gut feel, the Director of the Bureau believes the number of potential bidders can be predicted by five variables: the Class of oil found, the Miles from the oil field to the nearest distribution point, the Output potential of the well, the Geologist report, and the Size of the oil field. The director provides you with the last 30 leasing bids.

Bidders Class Miles output Geologist Size
300 1 8.0 5000 0.40 3.5
375 1 3.2 5000 0.40 4.0
200 1 8.0 4500 0.15 10.2
531 1 0.8 6500 0.50 1.3
115 1 12.0 3600 0.08 5.6
629 1 1.6 7800 0.65 2.9
152 1 5.9 4200 0.05 6.5
131 1 11.8 3600 0.05 9.8
192 1 4.0 2600 0.20 6.3
427 1 2.6 7800 0.35 10.1
93 2 25.0 7100 0.20 3.8
120 2 36.0 1500 0.25 4.2
46 2 17.8 3500 0.15 2.1
38 2 49.6 3800 0.15 1.6
29 2 48.3 5100 0.15 0.8
77 2 18.5 4200 0.20 2.8
102 2 17.1 5300 0.33 3.5
82 2 16.5 3100 0.25 3.0
53 2 26.1 4100 0.18 3.0
48 2 18.1 3400 0.15 2.3
10 3 135.1 3600 0.02 4.6
21 3 151.5 4500 0.04 10.1
16 3 80.5 3200 0.03 8.6
35 3 52.1 3900 0.05 16.1
40 3 51.6 4100 0.04 21.7
12 3 124.1 3600 0.01 2.2
15 3 103.1 4700 0.01 3.2
11 3 176.1 4300 0.02 2.0
19 3 142.6 3600 0.02 3.6
37 3 81.5 3100 0.04 4.2

The first column, Bidders, is what you are trying to predict based on the other five variables. The Director believes that the relationship between the five variables and the number of bidders is linear. Thinking back to your graduate school days and the QSO510 class, you know that you can solve this using a multiple regression technique. To solve this please answer the questions below.

#### Solution Summary

The solution provides step by step method for the calculation of multiple regression model. . Formula for the calculation and Interpretations of the results are also included.

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