What is the correct way to affirm a question that contains a negative?

That’s a a good question, and one that confuses new comers to North America (I don’t know if it’s all English speaking or just in North America) who are thinking “Yes, you’re right, I don’t think x” I guess an English teacher would say “No” is correct, but I’ve never read or heard about what is correct.

“That is correct/incorrect.”

I think the answer has more to do with the tone of the word than the word itself. There’s a way to say “no” that sounds like agreement (“no I don’t think that, you’re right”) and a way to say “no” that sounds like disagreement (“no, that’s not what I think”)—and same with “yes,” there’s a way to say it where it sounds like agreement (“yes, correct, I don’t think that”), and a way to say it that sounds like disagreement (“yes, yes I do think that, actually”). That’s been my experience, anyway, at least for spoken language.

^GA @Soubresaut

Yes! We have no bananas…

Logically, no should mean yes x and yes should be not x, but in nearly all cases where I have seen people answering, it is interpreted as being the same as if the person had asked, do you think x? And I agree that the responder should make explicit either x or not x.