Which of the following statements about multicollinearity is true? a. Multicollinearity occurs when two or more independent variables are highly correlated
b. Multicollinearity is usually not an issue when the regression model is only being used for forecasting
c. Multicollinearity is usually not an issue when the regression model is only being used to understand net relationships
d. Multicollinearity can typically be reduced by decreasing the sample size
e. Multicollinearity can typically be reduced by adding more independent variables

a. Multicollinearity occurs when two or more independent variables are highly correlated.

Step-by-step explanation:

Multicollinearity usuall occurs when an independent variables in a regression model is correlated. This correlation is a problem which occurs because independent variables should be independent. If the degree of correlation between variables is high enough, it would cause problems when you fit the models or try to interpret the results.

b.an increase in a causes b to decrease

answer: i don't understand it

step-by-step explanation: sorry