This is an excerpt from Organizing Successful Tournaments-4th Edition by John Byl.
Nine types of tournaments or leagues are described in this book: single elimination, double elimination, multilevel, straight round robin, round robin double split, round robin triple split, round robin quadruple split, semi–round robins, and extended (such as ladder and pyramid tournaments). In the passages that follow, you will find the details on each kind of tournament or league, including individual strengths and weaknesses and suggestions for the best use for each tournament and league format.
The greatest appeal of the single-elimination tournament is its simplicity. Losers are eliminated, and winners advance to the next round until only one contestant remains—the tournament champion. The single-elimination tourney is valuable when the number of entries is large, time is short, and the number of locations is limited. Of all the tournaments, this one requires the fewest games (or matches); however, half the participants are eliminated after one game, and only a quarter of the participants remain after the second round. When more extensive participation is important and more locations and time are available, a single-elimination tournament is probably not your best choice. Yes, a single-elimination format is the simplest, but the other tournaments described in this manual are also easy to organize, so the simplicity of single elimination is not a significant factor in its favor.
Probably the best use for the single-elimination tournament is play-offs at the end of a season or following a longer tournament, such as a split round robin. You would then determine seeding for the single elimination by the standings at the conclusion of the previous playing period. Single-elimination tournaments are discussed in depth in chapter 2.
The double-elimination tournament addresses two problems inherent in the single-elimination tournament. The first is that one of the best entries may have a bad first game or match or have been poorly seeded in the single-elimination draw; if that occurs in a single-elimination tournament, that entry is eliminated too soon. Having a losers' bracket gives such an entry an opportunity to play in the finals. The second problem with the single elimination is that half of the entries play only one game (or match). The double-elimination format ensures that all entries play at least two games.
However, this tournament type is often overrated because of those strengths. It also has weaknesses, and there are alternatives. The major difficulties with the double elimination are that the second- and third-seeded entries play many games, particularly in the final rounds of the tournament, and it takes many rounds to complete. Also, this tournament type often uses available areas inefficiently. For example, if the tournament consists of nine entries and four locations are available, the double-elimination tournament takes seven rounds to complete. This is as many rounds as in a round robin double split (discussed later) but without the advantages a round robin tournament offers.
The double elimination is a good option when the number of locations is limited, time is at a premium, final standings are important, and all entries are to be awarded a minimum of two games. For more on double eliminations, see chapter 4.
The multilevel tournament is similar to a single-elimination tournament; in fact, at the top level they are the same. However, in a multilevel tournament, a player is not eliminated following a loss but simply moves down one or more levels of play into the consolation rounds. This downward movement continues until no other challengers remain. One result of this approach is that all entries play about the same number of games. Another benefit is that in each round the players are more likely to encounter other players of their caliber.
In the final rounds of play in single- and double-elimination tournaments, only one or two locations are in use. This is not the case in the multilevel tournament. As a result, when sufficient locations are available, the multilevel tournament takes the same amount of time to complete as a single-elimination tournament and half the time of a double-elimination tournament. For example, if six locations are available, and the tournament contains 13 entries, it takes four rounds to complete the tournament using either the single elimination or the multilevel and eight rounds to complete a double elimination. The multilevel tournament is an excellent choice when equality in number of games played and closely contested matches are important, when time is limited, and when knowledge of third and subsequent final placements is not crucial.
This tournament is perhaps most useful in physical education classes or intramural or recreational settings where eliminating players is undesirable and final standings are of little significance. Because this tournament type offers many advantages in these situations, and because it may be new to the reader, we advise a review of chapter 3.
Straight Round Robin
The round robin tournament and league schedules consist of all individuals or teams playing each entry an equal number of times. The round robin and round robin split tournaments all use fixed schedules; all entries know exactly who they play and what time they play them, which offers advantage to entries in preparing for the tournament and upcoming games. Seeding does not affect the outcome because the cumulative results of all games played determine final standings. When the number of entries is small and games are played quickly (as in table tennis, badminton, or volleyball), this type of format is effective for a one-day tournament. When there are more entries and the games take longer to complete (as in hockey, football, or basketball), then a round robin schedule is best suited for league play. In this case, one time through a round robin provides the league schedule, and, if time permits, you could provide a home and away schedule simply by going through the round robin schedule twice.
The round robin format is not suitable for all situations. Because all entries play each other, a round robin format is problematic when the number of entries is high. For example, a tournament with 32 entries would take 496 games to complete using a round robin. This compares with 62 games in a double elimination and 31 in single elimination. Also, when there is considerable discrepancy in the caliber of play, many games or matches will prove unsatisfactory to all involved in these noncontests. For more on the regular round robin tournament and the other round robin formats discussed in the following paragraphs, see chapter 5.
The largest number of schedules on the accompanying website is for round robins. To help you find the schedule you want, the files have been divided into five main folders: 3–8 entries and 9–12 and 13–16 entries, locations shared and locations different. Within those folders, the files are further subdivided by type of round robin and by league. The league schedules have a home location. The other round robin schedules could also be used for league schedules in which entries share locations. For example, a community soccer league of 10 teams might share two soccer fields.
Round Robin Double Split
When a round robin format is desirable but the number of entries is too large, splitting the entries into two divisions is a practical solution. Following the play within the divisions, only the top two entries from each division participate in play-offs to determine the final top standings. The obvious benefit is that the number of games is halved. The drawback is that accurate seeding becomes important. For example, if the top three seeds are placed in one division and only the top two from each division advance to the play-offs, then (if entries perform consistent with their seedings) the third seed cannot play in the play-offs.
The round robin double split is commonly used for league play. You could split the league into two or more divisions, with the play-offs bringing together the top two teams from each division to decide the final standings.
Round Robin Triple Split
The round robin triple split is similar to the double split. However, because it would be awkward to have a single-elimination play-off with three or six finalists, a round robin format for the finalists is the most suitable. This requires more games in the play-offs and is a satisfactory alternative to the double split only when there are a very large number of entries.
Round Robin Quadruple Split
This type of tournament or league is intended to solve the same problems addressed by the double split, but instead of dividing the entries into two groups, they are divided into four groups. This is useful only when the number of entries exceeds 11. You could use this format in a one- or two-day tournament or in a league over a longer time. The major disadvantage of this approach is that when there are only 12 to 15 entries, the weaker players (or teams) might participate in only two games.
The semi–round robin is essentially a round robin tournament that solves the problem of uneven divisions. For example, in a baseball tournament with seven entries divided into two divisions, one division would have three entries, and the other would have four. This means that the division with four entries requires each team to compete in one more game than in the division with three entries. The semi–round robin corrects for this. This type of tournament is explained further in chapter 7.
Ladders and pyramids are two common examples of extended tournaments or leagues. Extended tournaments can be ongoing for an indefinite time or can be abbreviated to a week, a month, or another set period. For drop-in programs, such as intramurals or racket clubs, this tournament type can be most useful. Its major weaknesses are, first, that players challenge each other, which means that some players might not play as much, and, second, because of the challenge system, the ranking at the end of the tournament might not be accurate because some players may have played very few if any games. A round robin ladder tournament is presented in chapter 7; it combines the strengths of ladder-type tournaments with the fixed scheduling of round robin schedules. We discuss extended tournaments in detail in chapter 6.
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