Need Help From Surveyors/Statisticians

[Siegmund]

OK, a few more comments I'll toss out...

a) I used Schaeffer, Mendenhall, and Ott when I studied sampling. Not saying there's anything special about it, I assume that most any sampling book has the formulas in it. Under "a", two questions I would want to be prepared for: discuss the conditions under which a stratified sample gives you a much better estimate than a simple random sample does (perhaps other sampling schemes too - but you'll see simple and stratified more often than any other kinds); and discuss the advantages and hazards of systematic vs. random samples.

On b, you may want to separately address measurement bias as a result of badly written questions, vs. bias resulting from respondents not answering truthfully.
You might be given a loaded question in the interview, and asked how you word reword it more fairly.
There is quite a body of literature about how to get people to feel comfortable giving honest answers to crime- or sex-related questions. Not an area I've worked in though I've read a little about it.
I have had some experience with having to ask about something easily measureable as a proxy for something that isn't - for instance, asking someone how many days of work he has missed in the past month, rather than asking how many times he has been sick in the past month.

On c, the answer to most data-related things is post-stratification or some other kind of reweighting. If there was a sampling bias, you may be able to calculate something like P(being selected under the bad sampling method)/P(being selected under the right sampling method) to use as a weight. Stick to comments on nicely established methods to avoid sounding like you are making it up on the spot for the interview, but expect to need to make it up on the spot in your real life sometime.