Calculates the polyserial correlation coefficient between a continuous variable and an ordinal variable.
Arguments
- x
A numeric vector representing the continuous variable.
- y
A numeric vector representing the ordinal variable (must be integer values).
Value
A numeric value representing the estimated polyserial correlation coefficient.
Details
This function implements Olsson et al.'s ad hoc method for estimating the polyserial correlation
coefficient. The method assumes that the continuous variable follows a normal distribution and
that the ordinal variable is derived from an underlying continuous normal variable through
thresholds.
References
U.Olsson, F.Drasgow, and N.Dorans (1982).
The polyserial correlation coefficient. Psychometrika, 47,337-347.
Examples
n <- 300
x <- rnorm(n)
y <- sample(1:5, size = n, replace = TRUE)
polyserial(x, y)
#> [1] 0.100766
