# A simple linear regression was created to determine GPA based on hours studying per week. You want to know

1) A simple linear regression was created to determine GPA based on hours studying per week. You want to know if you spend 30 hours per week studying, what range you might expect your GPA to be in. What estimate do you need to calculate to find the range?

Answer

A. Confidence Interval Estimate

B. Point Estimate

C. Residual Interval Estimate

D. Prediction Interval Estimate

2)The Coefficient of Determination for a simple linear regression is 0.87 and the b1 came out to be -1.58. What is the Sample Correlation Coefficient and what does it mean?

Answer

A. -0.93 and it means there is a negative linear correlation between x and y.

B. 1.26 and it means there is a positive linear correlation between x and y.

C. -0.93 and it means there is no linear correlation between x and y.

D. 1.26 and it means there is no linear correlation between x and y.

3)The degrees of freedom used to calculate the p-value of the goodness of fit of a multinomial distribution is …

Answer

A. k-3

B. n-3

C. n-1

D. k-1

4)X-ray Express wants to simulate the arrival of requests. They think the arrivals per day follow a Poisson distribution and they have collected a sample of arrivals per day for 100 days to confirm. The information is provided in Figure 2 and the average number of arrivals is 1.2 for the 100 samples.

What is the chi squared statistic for the given information?

Answer

A. 4.29

B. 2.38

C. 25

D. 2.84

5)X-ray Express wants to simulate the arrival of requests. They think the arrivals per day follow a Poisson distribution and they have collected a sample of arrivals per day for 100 days to confirm. The information is provided in Figure 2 and the average number of arrivals is 1.2 for the 100 samples.

The p-value of the chi squared statistic is 0.304 and the desired alpha level is 0.05. Should X-Ray Express use a Poisson distribution in their simulation? (Does the data fit a Poisson distribution?)

Answer

A. No they cannot use a Poisson distribution because the null hypothesis is not rejected

B. Yes they can use a Poisson distribution because the null hypothesis is not rejected.

C. No they cannot use a Poisson distribution because the null hypothesis is rejected

D. Yes they can use a Poisson distribution because the null hypothesis is rejected

x= 16,29,29,48,56

y=11,13,14,17,20

that’s figure 1

6)Figure 1 contains information on annual income and years of education. The independent variable is years of education and the dependent variable is income.

Develop the least squares equation regression equation.

Answer

A. y(hat) = 4.5-31.9x

B. y(hat) = 35.6-15x

C. E(y) = 4.5x-31.9

D. y(hat) = -31.9+4.5x

7)Figure 1 contains information on annual income and years of education. The independent variable is years of education and the dependent variable is income.

Estimate the yearly income for an individual with 19 years of education.

Answer

A. $53,600

B. $249,400

C. -$601,600

D. $56,000

8)Figure 1 contains information on annual income and years of education. The independent variable is years of education and the dependent variable is income.

With an alpha of 0.05 what is the test statistic to determine if the slope (beta 1) is significant? Sb1=0.4374 If the p-value for the test statistic works out to be 0.00196 is the slope (beta 1) significant?

Answer

A. t-stat = 73.0 and it is significant.

B. t-stat = 10.3 and it is significant.

C. t-stat = 73.0 and it is not significant.

D. t-stat = 10.3 and it is not significant.

9)X-ray Express wants to simulate the arrival of requests. They think the arrivals per day follow a Poisson distribution and they have collected a sample of arrivals per day for 100 days to confirm. The information is provided in Figure 2 and the average number of arrivals is 1.2 for the 100 samples.

X-Ray Express wants to know during the 250 working days per year how many of those days they should expect to see 1 request arrive. (e^(-1.2)=0.3012) How many days per year should they expect to see 1 request arrive?

Answer

A. 36

B. 0.361

C. 90

D. 30