[I think that] where data are unavailable, you cannot really constrain your expectations of them. You can build models, even, perhaps, assign weights within them, but there is no basis to choose between one model and another, and every number of models you find 'satisfying' remains arbitrary.
(This is why I don't argue about religion, for example.)
This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.
To any future monthly posters of SQ threads, please remember to add the "stupid_questions" tag.