In: Statistics and Probability
For 5 students, scores on a math test (X) and statistics (Y) are given as follows:
X: 95 85 80 70 55
Y: 85 75 70 75 65
a) Fit the regression line
b) Test the model
c) Find the 90% Confidence Interval?
d) For a student who has a math score 75, estimate her/his statistics grade?
Regression Analysis | ||||||
r² | 0.724 | |||||
r | 0.851 | |||||
Std. Error | 4.495 | |||||
n | 5 | |||||
k | 1 | |||||
Dep. Var. | y | |||||
ANOVA table | ||||||
Source | SS | df | MS | F | p-value | |
Regression | 159.3817 | 1 | 159.3817 | 7.89 | .0674 | |
Residual | 60.6183 | 3 | 20.2061 | |||
Total | 220.0000 | 4 | ||||
Regression output | confidence interval | |||||
variables | coefficients | std. error | t (df=3) | p-value | 90% lower | 90% upper |
Intercept | 42.1237 | 11.53 | 3.65 | 0.04 | 15.00 | 69.25 |
x | 0.4140 | 0.1474 | 2.809 | .0674 | 0.0671 | 0.7609 |
Predicted values for: y | ||||||
90% Confidence Interval | 90% Prediction Interval | |||||
x | Predicted | lower | upper | lower | upper | Leverage |
75 | 73.172 | 68.391 | 77.954 | 61.563 | 84.781 | 0.204 |
a) Fit the regression line
y= 42.1237+0.4140x
b) Test the model
Since P value=0.0674>alpha(0.10) . We fail to reject the null hypothesis.
c) Find the 90% Confidence Interval?
(0.0671,0.7609)
d) For a student who has a math score 75, estimate her/his statistics grade?
73.172