Instead of the courtyard, we will be meeting at someone's house: please PM me, maia or PhilipL, and we'll send you the address. If you're subscribed to the mailing list (of course you are!) then you could also just look at it. It's very close to the Wheaton metro station. We will be doing measurement-based calibration games. That is to say, we'll be guessing the physical (or as Robin Hanson suggested, economic) properties of objects with confidence intervals, and then testing how well calibrated we are. If you have objects with properties (you probably do) and can bring them, please do so so we can guess at them. In particular, dense or (sparse?) objects would be interesting, as well as items that you know the price of.