On “paired prelim brackets”:
The idea here is that you “pair” 2 prelim brackets and play a “crossover” in each “pair”: each team in bracket A plays each team in bracket B, as opposed to each team in bracket A playing all the other teams in bracket A while each team in bracket B plays all the other teams in bracket B. Brackets are the normal size for quizbowl prelims (so, 6 to 8 teams).
You must have an even number of prelim brackets to do this format. If you do not have an even number, you should use a different prelim format or change your prelim bracket size so that there are an even number of brackets.
Brackets are paired such that the bracket with the overall #1 seed plays the bracket with the worst 1 seed (overall #4 if there are 4 brackets, overall #N for N brackets), and so on. As for a traditional round-robin prelim, brackets are created by “snake” seeding teams; then the brackets are “snake” seeded by #1 seeds for pairing.
- Creates more comparable records out of the prelims. In a normal round-robin, you can only rank teams within each bracket; in a paired system, A and B records are commensurable because they were generated by playing each other, while records within A can also be compared since all A teams played the same schedule.
- Reduces or eliminates the need for byes for certain field sizes. 7-team brackets play all 7 rounds instead of having a bye. Systems with some brackets of 7 and some of 6 can play with only one bye on the schedule (one per group of 7 team) as opposed to three (one per group of 7 and two per group of 6) as you would have to do in a round-robin. In particular, this covers the problematic 25-28 teams very well.
- Ensures more prelim rounds without rigamarole – paired brackets for 24 teams means every team gets 6 games in the prelims instead of 5, opening up some shorter / different playoff formats while still guaranteeing 9 games.
- In many field sizes, reduces the necessary length of a crossover playoff by 1 round. Every playoff team from tier X has already played M other playoff teams in tier X, where M is the number of playoff teams taken from each bracket to tier X. In a traditional round-robin, every playoff team from tier X has played M-1 teams from tier X because they only play teams from their own prelim group in the prelims and do not “play themselves”. This saves a round if there are an odd number of teams in prelim brackets (it does not save a round for even prelim brackets since prelims then take 1 extra round).
- Can require the same number of rooms as a bracketed round-robin prelims; for example, 26 teams with 7/6, 7/6 paired brackets requires 12 rooms.
- Seeding is much more important because you can have an unlimited number of 0 or 1 loss teams in a bracket. This is very different from a round-robin, where you have a maximum of 1 undefeated team, and a maximum of three 1-loss teams (and the only way to have multiple 1-loss teams is for them to all be tied for first). Any playoff format that is sensitive to this should remember that the mathematical maximums on 0 and 1 loss teams from round-robins do not apply here! This should not matter if your seeding is even a little bit careful – after all, most formats that start with round-robins also do not want to place multiple tournament-winning contenders in the same bracket because they also have to break a limited number of teams out of each prelim group. If you end up with the fifth-place team in a bracket standing at 1 loss because they beat teams 2-5 in their pair bracket, then you did your seeding very poorly or you had bad information about rosters; but, poor seeding and bad roster info do happen, so just like in any format, build in in safeguard making sure no team is needlessly screwed by it. The upshot of this is: take at least THREE teams from every bracket to the playoffs (whatever the playoff format might be) and not just two, especially if you are doing paper tiebreakers.
- If you have an odd number of teams in every bracket, extra rooms are required (and thus extra readers and extra etc.) – +1 room per pair of brackets. For example, 28 teams with 7/7, 7/7 paired brackets requires 14 rooms instead of 12. If you are hurting for staff, this is not the format for you.