Take the quiz test your understanding of the key concepts covered in the chapter. Try testing yourself before you read the chapter to see where your strengths and weaknesses are, then test yourself again once you’ve read the chapter to see how well you’ve understood.

1. What does a simple linear regression analysis examine?

The relationship between only two variables

The relationship between one dependent and one independent variable

The relationship between many variables

The relationship between two dependent and one independent variable

Answer:

a. The relationship between only two variables

c. The relationship between many variables

2. Which of the following are correct?

The intercept/constant (β_{0}) is the mean-Y when X=0

The intercept is the the amount of change in mean-Y when X=0

The coefficient is the mean-Y at a certain value of X

The coefficient (β) is the amount of change in mean-Y for every unit increase in X

Answer:

a. The intercept/constant (β0) is the mean-Y when X=0

d. The coefficient (β) is the amount of change in mean-Y for every unit increase in X

3. What does the least squares method do exactly?

Minimizes the distance between the data points

Finds the least problematic regression line

Finds those (best) values of the intercept and slope that provide us with the smallest value of the residual sum of squares

Finds those (best) values of the intercept and slope that provide us with the smallest value of the sum of residuals

Answer:

c. Finds those (best) values of the intercept and slope that provide us with the smallest value of the residual sum of squares

4. Which of the following measures is optimal for comparing the goodness of the fit of competing regression models involving the same dependent variable?

The intercept

The coefficient

R-square

Standard deviation of the residuals

Answer:

d. Standard deviation of the residuals

5. What does the following expression (H_{0}: _{1} = 0) mean?

Mean-Y changes as as a result of a change in X

Mean-Y does not change as a result of a change in X

Mean-Y value becomes 0 as a result of a change in X

Mean-Y value is equal to 0 when X=0

Answer:

b. Mean-Y does not change as a result of a change in X