A Balanced Bracket

On his website tournamentdesign.org, Joe Czapski has some ingenious tournament ideas.

One of his chief thoughts is to try to equalize the treatment of the upper and lower brackets in double- (and even triple- and quadruple-) elimination tournaments. He has a suite of Excel-based brackets for download. None of the ones I looked at looks like anything I’ve ever seen.

I’ve analyzed the “balanced” bracket for a 16-team double elimination so that I can relate it to the more conventional brackets already discussed. Continue reading “A Balanced Bracket”

The Results So Far

As promised in yesterday’s post, I ran simulations to see if the 32 bracket would behave the way the 16 bracket did, showing a fairness advantage for the unshifted format where the tournament is seeded. It did.

A number of these bracket simulations have been run now, and I thought it would be good to gather them together in one place so that they can be compared, and tentative inferences drawn. Continue reading “The Results So Far”

Seedy and Shiftless

Another surprising result today.

I ran a 16DE through the simulator, this time seeding the entries – all of my previous runs have been blind draw. On the basis of what I’ve seen so far, I decided to run only the shifted bracket, which is in line with my conclusion that the shifted bracket is, or at least should be, preferred. But there’s more to the story. Continue reading “Seedy and Shiftless”

Shifting a 32 Bracket

The bracket-shifting technique illustrated in the case of a 16 DE tournament can be generalized to larger brackets, but there are some additional considerations.

The bracket shift works, essentially, by taking two adjacent rounds of drops, which would ordinarily be separated in the lower bracket by a non-drop consolidating round, and pushing them into earlier rounds of the lower bracket, causing there to be one fewer round in the tournament as a whole.

In a 32 bracket, there are two ways to do this. You can either shift the C and D drops earlier, leaving the E drop in its usual relative position, or shift D and E drops earlier, leaving the C drops in place: Continue reading “Shifting a 32 Bracket”

Fairness for Everyone? Do We Need Another Measure?

There is unfinished business from the last couple of posts.

The remaining thing to do in addressing the question of whether a shifted bracket is a good thing or a bad thing is to address the question of whether it is bad because it uses an unbalanced bracket. Is an unbalanced bracket inherently unfair?

Before we do that, however, I want to consider whether it would be a good thing to consider a somewhat different coefficient that looks at the distribution of rewards short of winning the tournament as a whole.
Continue reading “Fairness for Everyone? Do We Need Another Measure?”

Building a Better Bracket, Part II

Yesterday I discussed a technique for squeezing a round out of the lower bracket in a double-elimination tournament by shifting some of the drops into early rounds. Now it’s time to discuss the other merits of that technique.

Here’s the bottom line: The round compression technique doesn’t just save a round so that the tournament runs faster, but it also improves overall fairness, and reduces the number of repeated pairings. It’s not just a plausible way to save some time in a round-intensive tournament, but it should probably be the technique of choice for almost any double-elimination tournament, whether or not there’s any benefit from running fewer rounds. Continue reading “Building a Better Bracket, Part II”

Getting the Drops Right, Part II

So, having made a case for the importance of putting the drops in the right places, let’s turn to the issue of how to get them there.

As a practical matter, the easiest thing to do is to download or copy from some source that can be relied upon to get it right. Unfortunately, there’s no site, other than this one, that I think can recommend on this point. I hope, in the fullness of time, to build out the collection of sample documents I make available here to the point where a tournament organizer can find a useful sample for any but the most exotic tournament. But don’t hold your breath. In the meantime, let me explain a general approach that I’ve found useful. Continue reading “Getting the Drops Right, Part II”