The data below is a sample of miles per gallon (mpg) and Engine horsepower (horsepower) of certain type of cars. Fit a least squares regression line of mpg on horsepower and test the significance of the model at 5% significance level.

Assignment4_table2.pdf

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mpg :23, 20, 33.8, 14, 26, 30, 24, 28.8, 18, 28, 17, 15, 29, 18.2, 33

horsepower :125, 100, 67, 165, 46, 68, 75, 115, 105, 90, 140, 130, 78, 135, 53

Using R programming and manually

(d) The intercept is

(e) The slope is

(f) The standard error of the slope is

(g) When horsepower is 120, the estimate of mpgis

(h) The F-test statistic for testing the significance of the regression model is

(i) The p-value for testing the significance of the regression model is

(j) The critical value for testing significanceof the model using the F test is

(k) The absolute value of the critical value for testing the significance of the model usingthe t-test is

(l) The upper bound forthe 95% confidence interval of the intercept is

(m) The correlation coefficient of mpg and horsepower is