Question

• Which of the following statements is incorrect? 
• A. The coefficient of determination is defined as r².
•  B. r indicates the strength and the direction of the relationship between X and Y variables.
•  C. If r²=0.70, it implies that 70% of the variation in Y is explained by the regression line.
•  D. If r=0.64 then r²=0.4096.
•  E. The coefficient of correlation r can never be negative.

Answer 1

Statement E is incorrect.

The coefficient of correlation r can be negative. A negative correlation describes the extent to which two variables move in opposite directions. For example, for two variables, X and Y, an increase in X is associated with a decrease in Y. A negative correlation coefficient is also referred to as an inverse correlation.