On sample size: 609 actually is not bad. In political research you could accurately predict an election off of that. PROVIDED... that your selection means was valid. The utility of a poll is 99% an issue of the means that was used to select respondants, and 1% the questions asked. * Your method must be as random as possible, and must avoid as much as possible any level of self selection in or out by the pollees. On the question of incomes. I find that to be a very valid question. This is a market survey attempt after all - and you need to know what income bracket you should be targeting. If you did a valid random sample survey, and it came back with a majority of users ina low income bracket, you could state that prices on places like renderosity might be too high. By contrast if it came back with a high income bracket, the reverse might be true. But these of course with have to be contrasted against the luxury spending budgets of the respondants and whether they use the product as a hobby or in professional needs. And etc... the market people around here could pick those kinds of questions better than me... I could tell you how to structure a political poll in the basic, given my education, and how to set it up for accuracy (which applies to both types). But I'm guessing for questions on a market poll. That said, it seems a sound guess than income is important.

Truth has no value without backing by unfounded belief.
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