All but one of the statements below contain a mistake. Which one could be true?
A) The correlation between gender and age is -0.171.
B) The correlation between weight and length of foot is 0.488.
C) The correlation between the breed of a dog and its weight is 0.435.
D) The correlation between height and weight is 0.568 inches per pound.
E) If the correlation between blood alcohol level and reaction time is 0.73, then the correlation between reaction time and blood alcohol level is -0.73.

Question

Quizplus · Accepted Answer

Correlation coefficients measure the strength and direction of a linear relationship between two variables on a scatterplot. The value of a correlation coefficient ranges from -1 to 1. Statement B is plausible because weight and length of foot can have a linear relationship, and 0.488 indicates a moderate positive correlation. The other statements contain mistakes: A) Gender and age are not quantitatively related in a way that would produce a correlation coefficient. C) The breed of a dog is a categorical variable, not quantitative, so it cannot have a correlation coefficient with weight. D) Correlation coefficients do not have units (inches per pound); they are unitless. E) The correlation between two variables is the same regardless of the order, so if it's 0.73 in one direction, it's also 0.73 in the reverse, not -0.73.

All but One of the Statements Below Contain a Mistake