The Yule coefficientis a correlation coefficient applied
to dichotomous data. Given a two x two table of counts
| a | b | R1 |
| c | d | R1 |
|C1 | C2| n |
or a vector c(a,b,c,d) of frequencies. Taken from psych::Yule.
Yule(x, Y = FALSE)
a 1 x 4 vector or a matrix 2 x 2 of frequencies.
if Y is true return Yule's Y coefficient of colligation.
the value of the Yule Q coefficient.
The coefficient of Yule is calculated from (ad - bc)/(ad + bc).
This is the number of pairs in agreement (ad) - the number in disagreement (bc)
over the total number of paired observations.
Yule, G.U. (1912). On the methods of measuring the association between two attributes. Journal of the Royal Statistical Society, 75, 579-652.
Warrens, Matthijs (2008), On Association Coefficients for 2x2 Tables and Properties That Do Not Depend on the Marginal Distributions. Psychometrika, 73, 777-789.