Skip to content

CA Foundation · Quantitative Aptitude · Correlation and Regression

For a bivariate data set the regression coefficient of y on x is –1.2. Which of the following could be the regression coefficient of x on y for the same data?

The answer is –0.5. Regression coefficients always share the sign of the correlation coefficient, and their product equals r², which cannot exceed 1. With byx = –1.2, bxy must be negative, and –0.5 gives r² = 0.6, which is valid.

  1. A–0.5Correct
  2. B+0.5
  3. C–0.9
  4. D+1.2

Explanation

Both regression coefficients must have the same sign, and their product r² must not exceed 1. With byx = –1.2, bxy must be negative. For –0.5, r² = 0.6, which is valid. For –0.9, r² = 1.08, which is impossible. The positive values have the wrong sign.

Did you get it right without looking?

One question tells you little. A timed set on Correlation and Regression shows your real accuracy, how long you take and where you lose marks.

Practise Correlation and RegressionFree diagnostic mock

More Correlation and Regression questions