The survey is long enough.that I'm unlikely to put genuine thought into each of the questions. If none of the answers us closer enough, I'm likely to skip the question. I'm likely to pick numbers it off thin air on any questions asking for a probability. I'm unlikely to actually dig up my SAT scores etc and will guess from memory. I will probably skip half of the bonus questions that Seth uninteresting because there are so many of them.

There are probably other people who are willing to run through the survey to help out but will spend a fixed and not too large amount of time on it. This is likely to introduce some bias and inaccuracy of answers given its current size. Just noting this as a set of trade offs to keep in mind.