[Campbell Biology P.727] The correlation coefficient 'r' quantifies the extent and direction... | Practice Question

The correlation coefficient 'r' quantifies the extent and direction of a linear relationship between two variables. Which of the following statements correctly describes the interpretation of 'r' values?

  • A: If r > 0, x and y are positively correlated, meaning that as x increases, y tends to increase.
  • B: If r < 0, x and y are positively correlated.
  • C: If r = 0, x and y are strongly correlated.
  • D: The value of r can range from 0 to 1 only.

Explanation

The text states: "The correlation coefficient indicates the extent and direction of a linear relationship between two variables x and y and ranges in value between -1 and 1. When r < 0, x and y are negatively correlated... When r > 0, x and y are positively correlated... When r = 0, the variables are not correlated."