Dag Asheim wrote:
My point is that this kind of pre-selection most likely will introduce a bias into the results in one way or another.
Indeed, although without General User Survey this is only a speculation, I believe that non-U.S. citizens form a very high minority (or even a majority) of English Wikipedia editors (which is, more or less, the International Wikipedia). To put it bluntly: a study that limits itself only to U.S. citizens because of budgetary restrains will be very significantly weakened. Please note that the cost of calling Skype to practially any line (fixed or mobile) outside US equals US local call, so seriously, budget should not be an issue (is there any way the Fundation could give a 'grant' for ~50$ for the study purposes? :).