[delinka]

While this operation may be statistically sound, it requires work. Humans are notoriously lazy when it comes to anything other than what they want to do. You'd be hard pressed to get each respondent to actually do this repetitively for an entire survey. Even if it had only three questions.

[msg]

For $50? College students have done much weirder and stupider stuff for less money than flipping a coin twice and answering a straightforward T/F question, even if it were twenty questions. The technique has been around for a long time. You should consider it a solved problem.

Finally googled the names. I also discovered the original formulations do it with only one coin flip (or one roll of a die).

http://en.wikipedia.org/wiki/Randomized_response

http://en.wikipedia.org/wiki/Unmatched_count

[delinka]

If you're offering $50 in cash to answer some questions and flip some coins, sure you'd get people to answer loads of them. But you're not offering an incentive to answer the questions.