'Whitened endogenous variable augmented with restriction parameters'

@property
def rwendog(self):

    if (self._rwendog is None):
        P = self.ncoeffs
        K = self.nconstraint
        response = np.zeros(((P + K),))
        response[:P] = np.dot(self.wexog.T, self.wendog)
        response[P:] = self.param
        self._rwendog = response
    return self._rwendog
