Correct Option
Option 2 (Point Biserial 'r')
Why this is correct:
Point Biserial Correlation ($r_{pb}$): Used when measuring the relationship between one continuous variable and one genuinely (truly) dichotomous variable. A genuine dichotomy is naturally occurring with no underlying continuity (e.g., dead/alive, pass/fail, yes/no).
Biserial Correlation ($r_b$): Used when the dichotomous variable is artificial—meaning it has an underlying normal distribution but was split artificially into two groups (e.g., separating people into "tall" vs "short" based on a cutoff height).
Tetrachoric Correlation: Used when both variables are artificially dichotomized continuous variables.
Phi Coefficient: Used when both variables are genuinely dichotomous.
Important Questions from Correlation Analysis
The value of simple correlation coefficient lies in the interval:
Which option is correct for the correlation ratio E 2?
Let θ be the angle made by the line of regression of Y on X. If σ Y= 2σ X and the correlation coefficient between X and Y is 0.3, the value θ equals
The multiple correlation coefficient R 1,23 as compared to any simple correlation coefficients between the distinct variable X 1 ,X 2, and X 3is
The coefficients of the regression β X|y and β Y|x , are known, The coefficient of correlation equals:
