High score seems to be good in terms of "My confident beliefs tend to be right."
Having your bars on the graph line up with the diagonal line would be an "ideal" graph (neither over- nor under- confident)
What is a high score? I realize that there is no absolute scale, but I have no idea if 10 is good or 1000 is bad.
Hey rationality friends, I just made this FAQ for the credence calibration game. So if you have people you'd like to introduce to it --- for example, to get them used to thinking of belief strengths as probabilities --- now is a good time :)