Starcraft AI blog

The AIST S1 results are out far ahead of schedule. I called the favorites as #1 McRave and #2 Tscmoo protoss. The winners turned out to be #1 PurpleSwarm and #2 McRave. Go zerg! But Steamhammer, the other zerg competitor, was the first to be eliminated.

We don’t get to see the games themselves until later. We do know the match results and the map order, so we can infer some of the specific game results.

The rules said that maps would be chosen randomly. I assumed that meant that the map order for each match would be chosen randomly, and games would cycle through the maps. But no, it was literal: For each game, a map was chosen at random. Some matches had repeated maps. For example, in the match McRave 2-0 Tscmoo, both games were played on Third World.

5 is an awkward number for an elimination tournament, as I said before. I expected 1 bye in the first round and 1 in the second, giving an advantage to the bye players. The bracket software instead gave 3 byes, so that the first winners round consisted of only 1 match, MadMix versus Steamhammer. These 2 players started at a disadvantage; if one of them was to come out on top of the winners bracket, it would have to win 1 more match than the 3 bye players. With 1 player in the losers bracket after 1 round, and 3 after 2 rounds, the losers bracket also needed to be split into 2 rounds, disadvantaging another player. MadMix could not be given another disadvantage, so Tscmoo got it.

The rules call for random seeding, so at least it’s fair on average—nobody has an advantage before seeding (only after). But there is no fair way to pair an elimination tournament with 5 players. Some competitors will always have an easier path than others. It’s hard to know when the byes make a difference in practice, but I notice that the 2 winners were the 2 players who were given no disadvantages.