How are you supposed to answer a question like this (assuming you're from Minnesota)?
You are a Minnesotan, no?
Are you supposed to give the same answer as your answer to this question or give the opposite answer?
You are a Minnesotan, yes?
Give the same answer as if it had a "yes" at the end. The "no" at the end means the person thinks the answer is probably "yes". (It's like saying "I'm pretty sure you are a Minnesotan, unless you take this opportunity to deny it.)
Unlike French and German, English does not have a word meaning "Yes, in contrast to what you have just asked or suggested". This does sometimes lead to confusion, but generally the answer is to the positive question, even where the question was asked negatively.
"Don't you want to go?"
"Yes" (I do)
"No" (I don't).
This tendency is if anything stronger where the negative is in a tag question, as here.