Yesterday, I thought the best talks I saw were by Devavrat Shah and Dina Katabi.
Dev was talking about how to track where rumors start. The model is you have a graph of nodes that have been infected (by a rumor, or disease, or whatever), and based on the the shape of that graph, you want to figure out where the process started. To get a picture of what I mean, suppose you were looking at a grid graph, and the infected area looked roughly like a circle. You'd expect the infection started somewhere near the middle of the circle. They've placed this in a mathematical framework (a distribution for the time to cross an edge, starting with tree graphs, etc.) that allows for analyzing these sorts of processes. This seems to be the arxiv version of the work.
Dina talked about 802.11n+, which they describe as "a fully distributed random access protocol for MIMO networks. 802.11n+ allows nodes that differ in the number of antennas to contend not just for time, but also for the degrees of freedom provided by multiple antennas." By making use of nulling and alignment, they can extend 802.11 so that instead of competing for time slots, multiple antenna systems can compete for degrees of freedom within a time slot, allowing those devices with multiple antennas to take full advantage (and in particular allowing them to overlap transmissions with devices with fewer antennas). I would have heard about it earlier, I guess, if I had gone to SIGCOMM this year. The project page is here.
There's a whole session this morning on "mean field analysis" and games. Mean field analysis (in my loose interpretation) means pretend your system gets big and turn it into a differential equation -- apparently a useful way to tackle various large-scale distributed agent/learning systems. It's what I used to study load-balancing systems way back for my thesis (and still find an occasional uses for today). Interesting to see it used for another set of problems. Ramesh Johari's student (I didn't catch which one) gave a talk on a really interesting model of dynamic auctions with learning where you could gain some real insight using a mean-field analysis. (How much should agents in an auction "overbid" when they're learning their value for winning an auction? It depends on how much they think they'll gain in the future based on what they learn about their true value.) This seems to be a preliminary version of the work.
Now for the "negative" -- something I'm going to suggest to the Allerton folks. It's time, I think, to find a different location. The Allerton conference center is very beautiful, but it's not suitable, in many respects, for this event any more. I was told there were about 330 registered attendees from outside UIUC, plus an additional 120 or so from UIUC. It's a bit hard to turn that into a true count; many (most?) UIUC people probably drop by 1 day, most attendees probably 1.5-2 days of the three. But Allerton really wasn't designed for a crowd that large. If you're not in one of the "big rooms", and people want to come to your talk, many times they can't get in. For example, the social network session was remarkably popular; the room could seat 40 people, and there were about 20+ people crowded around and outside the doorway -- which was not only not ideal, but it was also disruptive, as the open door meant a lot of noise in the room. Actually, the acoustics aren't particularly good in any of the rooms, even the big ones. Attendance in the early am is very low, in part I think because people staying "in town" have a non-trivial drive to get to Allerton.
When the event was smaller, like 200-250 people, everyone coped with these problems. It's really not working now.
I can understand there's an attachment to the Allerton center -- and how could it be the "Allerton conference" (next year is it's 50th year!) if it wasn't at Allerton? But this has been an issue for years, and only seems to get worse. There must be a conference venue on or near UIUC campus that would work as well -- at the very least, my opinion is it's time to look....
And now, back to the airport...