To understand what more is needed beyond statistical goodness of fit, it is worth recalling that, at its heart, science is the making and testing of hypotheses. In a Rietveld refinement, the immediate hypothesis being tested is whether the model loaded in the software, together with the profile and background functions, mathematically fits the experimental data. But for practical purposes that is never the entire hypothesis under examination by the scientist; they are concerned with broader questions. As we have seen in the discussion above, if the wider claim is that a new material has been discovered, it is not enough to show a good match between the new material and the data -the fit must be better than that obtained for known materials that are likely to be present.