docs: @Override
    public ListSufficientStatistics getNewSufficientStatistics() {
      List<SufficientStatistics> sufficientStatistics = Lists.newArrayList();
      for (ParametricFactor factor : getParametricFactors()) {
        sufficientStatistics.add(factor.getNewSufficientStatistics());
      }
      return new ListSufficientStatistics(factorNames.items(), sufficientStatistics);
    }