def plot_scales(self, titles=None, fig_kwargs={}, **kwargs):
        """
        Plot input sensitivity for all datasets, to see which input dimensions are
        significant for which dataset.

        :param titles: titles for axes of datasets

        kwargs go into plot_ARD for each kernel.
        """
        from ..plotting import plotting_library as pl

        if titles is None:
            titles = [r'${}$'.format(name) for name in self.names]

        M = len(self.bgplvms)
        fig = pl().figure(rows=1, cols=M, **fig_kwargs)
        for c in range(M):
            canvas = self.bgplvms[c].kern.plot_ARD(title=titles[c], figure=fig, col=c+1, **kwargs)
        return canvas