SAS and SPSS are general statistical packages. PATN specialises in the exploratory aspects of statistics (pattern finding, hypothesis generation), not the confirmatory part (hypothesis testing) such as modelling.
PATN has association measures that are proven to recover underlying structure far better than the usual ones available in stats packages (eg Bray and Curtis, Kulczynski and two-step). Also, PATN’s custering techniques (both non-hierarchical and hierarchical) are adapted to maximise recovery by linking to known characteristics of the association measures. Ditto the ordination technique in PATN; SSH This is a hybrid of BOTH metric and non-metric scaling and is well proven over both traditional methds such as factor and principal components/coordinates.
But, aside from the ‘engines’ inside PATN, the real difference is in HOW PATN interacts with the user. A (very) complete analysis in PATN takes about a minute from the time you import data till the time you have the results. PATN scans incoming data and picks an analysis stratgey. general packages cannot do that. This is literally the trivial part of PATN (but as stated above, it is a ‘robust’ part).
The really interesting – and fun partit is the interactive 3d display where you really get to understand the patterns. This is where he results all come together into one dynamix, interactive display. As far as I am aware, there is no statistical package that goes anywhere near PATN in interactive visualization. If you havent experienced this, it’s hard to explain what it is like. The interrogation/evaluation options on this display are very powerful in getting users to think about data structures, causes, processes. It is here were most PATN users spend 99% of their time. Correctly so. This is how PATN v3 was designed.
Hope that helps a little. I could say a lot more about the differences (natural colour, object comparisons, association histograms…) but I’d be interested to see what other PATN users would say.