1. The superintendent of a school district wanted to predict the percentage of students passing a sixth-grade proficiency test. She obtained the data on percentage of students passing the proficiency test (% Passing), mean teacher salary in thousands of dollars (Salaries), and instructional spending per pupil in thousands of dollars (Spending) of 47 schools in the state. Following is the multiple regression output with Y=% Passing as the dependent variable, X1=Salaries and X2=Spending.
Regression Statistics
Multiple R 0.4276
R Square 0.1828
Adjusted R Square 0.1457
Standard Error 5.7351
Observations 47
ANOVA
df SS MS F Significance F
Regression 2 323.8284 161.9142 4.9227 0.0118
Residual 44 1447.2094 32.8911
Total 46 1771.0378
Coefficients Standard Error t Stat P-value Lower 95% Upper 95%
Intercept -72.9916 45.9106 -1.5899 0.1190 -165.5184 19.5352
Salary 2.7939 0.8974 3.1133 0.0032 0.9853 4.6025
Spending 0.3742 0.9782 0.3825 0.7039 -1.5972 2.3455