Question 16 (1 point) Consider regressing the number of pages in a book versus t
ID: 3050969 • Letter: Q
Question
Question 16 (1 point)
Consider regressing the number of pages in a book versus the number of words in a book. The data would have _______________ correlation.
Question 16 options:
positive
negative
no
undetermined
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Question 17 (1 point)
A correlation coefficient, r, of 0.65 is stronger than a correlation coefficient of -0.65.
Question 17 options:
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Question 18 (1 point)
Choose the value of the Pearson's Correlation Coefficient (r) that best describes the two plots.
Question 18 options:
I: 0.179, II: 0.101
I: 0.821, II: 0.899
I: 0.101, II: 0.821
I: -0.821, II: -0.101
I: 0.821, II: 0.101
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Question 19 (1 point)
Suppose we would like to nd a relationship between the number of credits a student is enrolled in (X) and how many hours they work a week (Y ). Suppose the average number of credits a student is enrolled in is 13.2 with a standard deviation of 2.5 and the average number of hours a student works a week is 7.8 with a standard deviation of 4.2. The correlation between these two variables is 0.42. Calculate the regression equation for the data.
Question 19 options:
Y=-1.57-0.71X
Y=17.17+0.71X
Y=17.17-0.71X
Y=15.15-0.25X
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Question 20 (1 point)
Suppose we would like to nd a relationship between the number of credits a student is enrolled in (X) and how many hours they work a week (Y ). Suppose the average number of credits a student is enrolled in is 13.2 with a standard deviation of 2.5 and the average number of hours a student works a week is 7.8 with a standard deviation of 4.2. The correlation between these two variables is 0.42. Predict the number of hours a student works if they are enrolled in 15 credits.
Question 20 options:
10.8
9.1
6.5
5.6
positive
negative
no
undetermined
Explanation / Answer
16)positive
17) False ; only direction is invert
18) corect option is I: 0.821, II: 0.101
19)b1 =r*Sy/Sx =-0.42*4.2/2.5=-0.71
bo =Ybar -b1*Xbar =7.8-(-0.71)*13.2=17.17
Y=17.17-0.71X
20)predicted score =17.17-0.71*(15)=6.5