EPTThe original question I wanted to answer is as follows:
Many tournaments allow losing players to pick the next map, so which map should I pick?
To solve this question I grabbed my graphing calculator (and a spreadsheet) and began to input data. I needed a fairly large source of data to pull from, but I also wanted to avoid any inaccuracies caused by much better players stomping on worse players. While those samples are statistically significant, they indicate the need for a much larger data set. Ultimately, I chose to go with TLPD's data on a per map basis. Some of my more preliminary work can be found here: http://gaming.stackexchange.com/questions/15526/what-are-the-terrans-best-and-worst-1v1-maps/15550#15550
You can find this data here: http://www.teamliquid.net/tlpd/tlpd_select.php
My spreadsheet is here: https://spreadsheets.google.com/ccc?key=tsdNUMXQu6hIurnQigHkGTQ&authkey=CMX1050H#gid=0
Almost immediately you'll notice that no map is considered "Balanced." As a threshold for Balanced/Imbalanced I decided to require a statistical 95% confidence. Many scientific journals require P < .1 or P < .05 (90% and 95% respectively), so I feel this is a good number. As you can see, there is no map which has a P value greater than .95, thus there is no map which I am 95% or greater confident that it is balanced.
Based on this, the remainder of the data falls into two categories: Maps which may or may not be balanced, and maps which are imbalanced.
A closer look at the data will also reveal the following fact: Zerg's lose a lot. Based on my sample data ZvP is 47.6% win rate and ZvT is 44.1% win rate. Initially I assumed that a Balanced map would have a 50% win rate for all races, but the result is that all maps came up imbalanced against Zerg. As a result I had to recalculate my data based on the observed Zerg win rate. When we take that in to account we see there are a number of maps where Zerg have an unusually high win rate (though not necessarily better than 50%). One could argue that means all maps are imbalanced against Zerg, only some less so, but that sort of argument is irrelevant in answering my original question. I only seek to identify the maps which are most likely to provide an advantage from the pool.
With out further ado here is your tl;dr; the following maps are most likely Imbalanced:
1) TvZ Xel'Naga (favoring Terran) at 99.97% confidence
2) ZvT Shakuras (favoring Zerg) at 99.96% confidence
3) ZvP Blistering Sands (favoring Zerg) at 99.92% confidence
4) PvT Xel'Naga (favoring Protoss) 99.8% confidence
5) ZvT Blistering Sands (favoring Zerg) 98.6% confidence
Probably the most shocking map on this list is Xel'Naga which favor's Terran against Zerg and Protoss against Terran (PvZ is not significantly different from standard). There isn't a lot of literature that points to Zerg doing poorly on Xel'Naga, but is it the most likely map to be imbalanced against them.
Another interesting map is Blistering Sands. It seems in both match ups it favors Zerg. This is strange as Blistering Sands is frequently quoted as a map with a fairly short rush distance, but it turns out that distance is still fairly long (~40 seconds), and an easily defensible natural seem to put this map more in favor of the Zerg. Another worthwhile point to notice is the ease of Overlord scouting. The horse shoe shaped main, leaves many angles for an overlord to squeeze in.
A map which didn't make the list (but deserves honorable mention) is Metalopolis. While still not a great map for Zerg the confidences were 9.85% and 12.1% (for PvZ and PvT). Though I can't say with statistical certainty that this is a bad map for Zerg, gut instinct tells me that those numbers are very low. I've written about Metal before (http://www.teamliquid.net/forum/viewmessage.php?topic_id=179183) though my original measurements assumed that Zerg should win 50% of the time (instead of the 45% of the time they win on average across all maps).
Because no map had a P value greater than .95, I can't say with statistical certainty that any map is Balanced, however, I can list the maps which are more likely balanced:
1) PvT on Blistering Sands (86.5% confident)
2) ZvP on Shakuras (82.5% confident)
3) ZvP on Lost Temple (74.0% confident)
4) PvT on Metal (73.2% confident)
Edit: here is the data for patch 1.2 only: https://spreadsheets.google.com/ccc?key=0Am57dGT4LkjRdHVWcDMxLXFqSlFVOVJfS3hwazluZHc&hl=en&authkey=CJCVoeUL
