Correlation and regression quiz

If the coefficient of determination (R-squared) is 0.75, what does it indicate?

• 75% of the data points lie on the regression line

• The regression model is not valid

• There is no relationship between the variables

• 75% of the variability in the dependent variable is explained by the independent variable

If the correlation coefficient is -0.90, what can be inferred about the relationship between the variables?

• Strong negative correlation

• Weak negative correlation

• No correlation

• Perfect negative correlation

The situation where the independent variable increases, and, on average, the dependent variable decreases is referred to as:

• No relationship

• A nonlinear relationship

• A positive linear relationship

• A negative linear relationship

In simple linear regression, what is the role of the dependent variable?

• It is the variable being manipulated

• It is the variable used for prediction

• It is the variable being predicted

• It is the variable used for comparison

What does the slope coefficient in a simple linear regression equation represent?

• The change in the dependent variable for a one-unit change in the independent variable

• The intercept of the regression line

• The correlation between the variables

• The average value of the dependent variable

What is the primary difference between simple linear regression and multiple linear regression?

• The type of dependent variable

• The number of independent variables

• The level of significance

• The range of data values

What does Root Mean Square Error (RMSE) measure in the context of regression models?

• The percentage error between predicted and actual values

• The correlation between independent and dependent variables

• The accuracy of the model intercept

• The average squared difference between predicted and actual values

What does the term "adjusted R-squared" take into account that the regular R-squared does not?

• The number of independent variables

• The type of dependent variable

• The number of observations

• The level of significance