An independence working dependence structure.
Methods
| covariance_matrix(expval, index) | Returns the working covariance or correlation matrix for a given cluster of data. |
| covariance_matrix_solve(expval, index, ...) | Solves matrix equations of the form covmat * soln = rhs and returns the values of soln, where covmat is the covariance matrix represented by this class. |
| initialize(model) | Called by GEE, used by implementations that need additional setup prior to running fit. |
| summary() | |
| update(params) | Updates the association parameter values based on the current regression coefficients. |