Question

Does spending time online affect a student's test score? For a sample of students, the hours spent online X during a weekend and the score on a test Y the following Monday were used to construct a linear regression prediction model. Here are some results.

y= -4.07x+93.9

r = -.831

r2 = .691

a. State the coefficient of determination? Interpret this number in the context of this problem.

b. Based on the information here, would you consider hours spent online to be a good predictor of test score? Explain why or why not.

Answer 1

a. State the coefficient of determination? Interpret this number in the context of this problem.

The coefficient of determination or the value of R square is given as 0.691 which means about 69.1% of the variation in the dependent variable score on a test (y) is explained by the independent variable hours spent online (x).

b. Based on the information here, would you consider hours spent online to be a good predictor of test score? Explain why or why not.

Based on the above information, we would consider hours spent online to be a good predictor of test score because about 69.1% of the variation in the dependent variable score on a test is explained by the independent variable hours spent online. Given percentage of explaining the variation is considerably high.