Statistics Regression & Correlation Analysis

Question 1

What does the correlation coefficient r = 0 indicate?

Accepted Answer

No linear relationship between the two variables

Answer

A perfect negative linear relationship

Answer

A perfect positive linear relationship

Answer

A non-linear relationship exists

Question 2

In simple linear regression, what does the slope coefficient represent?

Accepted Answer

The average change in Y for a one-unit increase in X

Answer

The value of Y when X equals zero

Answer

The correlation between X and Y

Answer

The standard deviation of the residuals

Question 3

What does the coefficient of determination R² represent?

Accepted Answer

The proportion of variance in Y explained by the regression model

Answer

The correlation coefficient squared only for perfect fits

Answer

The probability that the regression is significant

Answer

The slope divided by the standard error

Question 4

What is a residual in linear regression?

Accepted Answer

The difference between observed and predicted values

Answer

The slope of the regression line

Answer

The intercept of the regression equation

Answer

The standard deviation of X

Question 5

Which of the following is the correct range for the Pearson correlation coefficient r?

Accepted Answer

−1 to +1

Answer

0 to 1

Answer

−∞ to +∞

Answer

0 to +∞

Question 6

In multiple regression, what does multicollinearity refer to?

Accepted Answer

High correlation among predictor variables

Answer

Non-linear relationship between predictors and outcome

Answer

Unequal variance of residuals

Answer

Outliers in the response variable