> Any stats showing they are hurt by the closed nature of their software? No reliable statistics, only the conjecture that Sage, sympy and other such environme

> Any stats showing they are hurt by the closed nature of their software? No reliable statistics, only the conjecture that Sage, sympy and other such environments allow people to produce a significant percentage of the results Mathematica can produce. Mathematica still has a substantial territory of advanced results unmatched by the free environments, but the gap is narrowing as the years pass. I know this -- students are much more likely to acquire Sage or IPython than purchase even the lower-priced student version of Mathematica, simply because they can get the former for free, and there's plenty of high-quality documentation and examples available (example http://arachnoid.com/IPython http://arachnoid.com/IPython). And how many undergraduate courses require the kinds of advanced results that only Mathematica can produce? And given those specific results, in an academic environment how much of a penalty is it that only the result is produced with no explanation or context?