It is believed that GPA (grade point average, based on a four point scale) should have a positive li
Question: It is believed that GPA (grade point average, based on a four point scale) should have a positive linear relationship with ACT scores. Given below is the Excel output from regressing GPA on ACT scores using a data set of 8 randomly chosen students from a Big Ten university.
Regressing GPA on ACT |
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| Regression Statistics | ||||||
| Multiple R | 0.7598 | |||||
| R Square | 0.5774 | |||||
| Adjusted R Square | 0.5069 | |||||
| Standard Error | 0.2691 | |||||
| Observations | 8 | |||||
| ANOVA | ||||||
| df | SS | MS | F | Significance F | ||
| Regression | 1 | 0.5940 | 0.5940 | 8.1986 | 0.0286 | |
| Residual | 6 | 0.4347 | 0.0724 | |||
| Total | 7 | 1.0287 | ||||
| Coefficients | Standard Error | t Stat | p-value | Lower 95% | Upper 95% | |
| Intercept | 0.5681 | 0.9284 | 0.6119 | 0.5630 | -1.7036 | 2.8398 |
| ACT | 0.1021 | 0.0356 | 2.8633 | 0.0286 | 0.0148 | 0.1895 |
(a) State the regression equation.
(b) Interpret the meaning of b0 and b1 in this problem.
(c) What is the predicted average value of GPA when ACT = 32?
(d) At the 0.05 level of significance, is there evidence of a linear relationship between the GPA and ACT?
(e) Construct a 95% confidence interval estimate of the population slope β1. Interpret the confidence interval estimate.
(f) How useful do you think this regression model is for predicting GPA?
Price: $2.99
See Answer: The solution file consists of 2 pages
Deliverables: Word Document
Deliverables: Word Document
