def delta_dissemination(self) -> np.array:
        '''
        Returns a novel variation of dissemination metric D_w from Altmann et al. 2011
        where the expected dissemination is subtracted from the observed. This is more
        suited for plotting.
        '''
        U_w, Utilde_iw = self.__dissemination_components()

        return (U_w - Utilde_iw.sum(axis=0).A1).A1

        Returns a novel variation of dissemination metric D_w from Altmann et al. 2011
        where the expected dissemination is subtracted from the observed. This is more
        suited for plotting.
        
scattertext/dispersion/dispersion.py