def get_mean_and_stddevs(self, sites, rup, dists, imt, stddev_types):
        """
        See :meth:`superclass method
        <.base.GroundShakingIntensityModel.get_mean_and_stddevs>`
        for spec of input and result values.
        """
        # extracting dictionary of coefficients specific to required
        # intensity measure type.
        C = self.COEFFS[imt]
        mean = (self._compute_style_of_faulting_term(rup, C) +
                self._compute_magnitude_scaling(rup.mag, C) +
                self._compute_distance_scaling(dists.rjb, C) +
                self._compute_site_term(sites.vs30, C))

        stddevs = self._get_stddevs(C, stddev_types, num_sites=len(sites.vs30))

        return mean, stddevs
See :meth:`superclass method
        <.base.GroundShakingIntensityModel.get_mean_and_stddevs>`
        for spec of input and result values.