[BobK]

Insufficient information.

There are many different situations.

Was it raised?

If so, who raised and from what position?

What is the top pair? Makes a differences how they perceive your hand.

Who's new to the table? You or them.

If you're new, what kind of image do you want to project to the table as a whole?

Could they have a flush draw with their pair?

Could they legitimately have a reason to think you don't have top pair, or maybe a weak kicker if an unraised pot?

As you can see, there are many things to consider.

After the first round or two you should have sufficient knowledge of the players to be able to start fine tuning your decisions. If you change tables so often you can't get a read, I would suggest just folding since most players aren't check raising without having top pair beat. It will keep your deviation down, but may not be as profitable as having a good read on your opponent.