PhiCoefficient {exametrika} | R Documentation |
Phi-Coefficient
Description
The phi coefficient is the Pearson's product moment correlation coefficient between two binary items. This function is applicable only to binary response data. The coefficient ranges from -1 to 1, where 1 indicates perfect positive correlation, -1 indicates perfect negative correlation, and 0 indicates no correlation.
Usage
PhiCoefficient(U, na = NULL, Z = NULL, w = NULL, ...)
Arguments
U |
U is a data matrix of the type matrix or data.frame. |
na |
na argument specifies the numbers or characters to be treated as missing values. |
Z |
Z is a missing indicator matrix of the type matrix or data.frame |
w |
w is item weight vector |
... |
Internal parameters for maintaining compatibility with the binary data processing system. Not intended for direct use. |
Value
A matrix of phi coefficients with exametrika class. Each element (i,j) represents the phi coefficient between items i and j. The matrix is symmetric with ones on the diagonal.
Note
This function is implemented using a binary data compatibility wrapper and will raise an error if used with polytomous data.
Examples
# example code
# Calculate Phi-Coefficient using sample dataset J15S500
PhiCoefficient(J15S500)