In: Statistics and Probability
A statistical program is recommended.
A marketing professor at Givens College is interested in the relationship between hours spent studying and total points earned in a course. Data collected on 10 students who took the course last quarter follow.
Hours Spent Studying |
Total Points Earned |
---|---|
45 | 40 |
30 | 35 |
90 | 75 |
60 | 65 |
105 | 90 |
65 | 50 |
90 | 90 |
80 | 80 |
55 | 45 |
75 | 65 |
(a)
Develop an estimated regression equation showing how total points earned can be predicted from hours spent studying. (Round your numerical values to two decimal places.)
ŷ =
(b)
Test the significance of the model with α = 0.05. (Use the F test.)
State the null and alternative hypotheses.
H0: β0 = 0
Ha: β0 ≠ 0
H0: β0 ≠ 0
Ha: β0 = 0
H0: β1 = 0
Ha: β1 ≠ 0
H0: β1 ≠ 0
Ha: β1 = 0
H0: β1 ≥ 0
Ha: β1 < 0
Find the value of the test statistic. (Round your answer to two decimal places.)
Find the p-value. (Round your answer to three decimal places.)
p-value =
State your conclusion.
Do not reject H0. We cannot conclude that the relationship between hours spent studying and total points earned is significant.
Reject H0. We conclude that the relationship between hours spent studying and total points earned is significant.
Do not reject H0. We conclude that the relationship between hours spent studying and total points earned is significant.
Reject H0. We cannot conclude that the relationship between hours spent studying and total points earned is significant.
(c)
Predict the total points earned by Mark Sweeney. He spent 85 hours studying. (Round your answer to two decimal places.)
points
(d)
Develop a 95% prediction interval for the total points earned by Mark Sweeney. (Round your answers to two decimal places.)
points to points
y = 5.85 + 0.83 x
b)
SUMMARY OUTPUT | ||||||||
Regression Statistics | ||||||||
Multiple R | 0.936862 | |||||||
R Square | 0.87771 | |||||||
Adjusted R Square | 0.862424 | |||||||
Standard Error | 7.523125 | |||||||
Observations | 10 | |||||||
ANOVA | ||||||||
df | SS | MS | F | Significance F | ||||
Regression | 1 | 3249.721 | 3249.721 | 57.41819 | 6.44E-05 | |||
Residual | 8 | 452.7792 | 56.59741 | |||||
Total | 9 | 3702.5 | ||||||
Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | Lower 95.0% | Upper 95.0% | |
Intercept | 5.847009 | 7.971731 | 0.733468 | 0.48421 | -12.5358 | 24.22985 | -12.5358 | 24.22985 |
X Variable 1 | 0.829539 | 0.109474 | 7.577479 | 6.44E-05 | 0.577091 | 1.081988 | 0.577091 | 1.081988 |