When predicting Y from two variables relative to using only one variable, _________.
A) prediction accuracy always increases
B) prediction accuracy is dependent on the relationship between the second variable and the Y variable
C) increase in prediction accuracy depends on the correlation between the two predictor variables
D) b and c

Question

Quizplus · Accepted Answer

Prediction accuracy is not always guaranteed to increase when using two variables instead of one. It depends on the correlation between the two predictor variables and the relationship between them and the Y variable. Therefore, options B and C are both correct and the best answer is D which accounts for both.

When Predicting Y from Two Variables Relative to Using Only