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I attached one Image. Do any two problems from 4.5, 4.6 and 4.9 for part 1. and for part 2 i attached the excel file and part 2 needs to be done in R. Upload R file and word file when you are done.

Homework #2

## Part 1 (4 Points):

· Choose 4 of the 5 questions to answer.

· I will grade the first five questions you answer. For example: if you answer #1-7, I will grade #1-5 (the first five). If you answer #2-7, I will grade #2-6 (the first five).

· Each question is worth 2 points. Zero points will be assigned for questions without answer

Questions:

4.2A, 4.2B, 4.5, 4.6, 4.9,

## Part 2 (6 Points):

All Calculations must be done in R using the excel document “Gas_Consumption.xlsx”:

1) Plot X=Income and Y=Gas Consumption.

2) Describe plot #1 and what you notice about the plot?

3) Calculate the Regression Line of #1.

4) Is the X-variable statistically significant?

5) What does the intercept mean?

6) Explain the sign of the intercept and coefficients.

4.2 A random sample of 200 20-year-old men is selected from a population and these men’s height and weight are recorded. A regression of weight on height yields ——-Weight = -99.41 + 3.94 x Height, R2 = 0.81, SER = 10.2,

where Weight is measured in pounds and Height is measured in inches.

a. What is the regression’s weight prediction for someone who is 70 in. tall? 65 in. tall? 74 in. tall?

Sol: For Height of 70 in

Prediction weight = -99.41+3.94*70 = 176.39 Pounds

For Height of 65 in

Prediction weight = -99.41+3.94*65 = 156.69 Pounds

For Height of 74 in

Prediction weight = -99.41+3.94*74 = 192.15 Pounds

4.2 ) b) A man has a late growth spurt and grows 1.5 in. over the course of a year. What is the regression’s prediction for the increase in this man’s weight?

Sol: The weight would be predicted to increase by = 1.5*3.94 = 5.91 Pounds