The single elimination system is to organize the contestants (teams) into a certain competition, and the adjacent players (teams) compete, and the negative team is eliminated and the winner is promoted. This kind of game is widely used in tennis. Its characteristics are: short time, easy arrangement, simple ranking, but poor rationality.
1. Holiday arrangement
When the number of athletes participating in the competition is 2, 4, 8, 16, 32, 64 and 128, the competition can be held according to the corresponding number. If the number is not a power of 2, there will be a bye in the first round. The calculation method is as follows: select the power closest to the number of participants and greater than the number of participants 2 as the number, then if there are 27 athletes participating in the competition, select 32 numbers, and 32 minus 27 is 5, so the five numbers will be bye-bye, and the players who meet these five numbers will bye-bye and directly enter the second round.
The principle of placing the bye position is that the seeded players are the first, and the areas without the seeded players are decided by drawing lots. If the number of bye bits is odd, one more bye bit should be put in the upper part.
2. Seed identification and arrangement
In order to ensure that high-level players will not meet prematurely, we should set the corresponding players as seed players according to their rankings and arrange them in different areas reasonably to reduce speculation in the competition. The specific number of seeds (1/4 digits) is determined as follows:
Players with 8 players or less have 2 seeded players;
Players under 16 should have 4 seed players;
There are 8 seeded players under 32 people;
Players under the age of 64 have 16 seed players;
128 The following players have 32 seed players …
The 1 seed is arranged at the position of 1, and the No.2 seed is arranged at the bottom. Or 16, 32, 64, 128. Other seeds are pumped in the next day, first into the upper part and then into the lower part, as shown below:
3. Arrangements for non-seeded players
Number the unseeded players, and draw lots in sequence except for the positions occupied by seeds and bye.
4. Special provisions
In some competitions, it is necessary to avoid players from the same unit from appearing in the same 1/4 area as much as possible, so it is reasonable to manually control the placement of seed players and the lottery of non-seed players.
5. Calculation of rounds and fields
The number of rounds is the number of teams (people) is 2, not how many rounds. If there are 16 people, it is 2 to the fourth power, and there are 4 rounds. If there are 17 players, it should be arranged according to the principle of not arranging the number grab, so there are 5 rounds (only one ball in the first round).
Number of games = number of participants-1
Second, single cycle system.
The single round robin system is a competition mode in which each team (person) has to compete and the ranking is determined by points. This method can be used in the case of few teams (people), many venues and long cycle. Features are: reasonable, can participate in more competitions and accumulate experience.
Every opponent's appearance is a "round", and the number of times in each round is the same.
1. Count the number of rounds and matches.
(1) Round number calculation
When the number of teams (people) is even, the number of rounds is equal to the number of teams (people) minus1;
When the number of teams (people) is an integer, the number of rounds is equal to the number of teams (people).
(2) Calculation of matching quantity
Venue = teams (people) * (number of teams (people)-1)/2
2. Determination of competition order
Generally, the counterclockwise wheel method is adopted, that is, the number 1 is fixed. In the first round, the first half of the number of teams (people) is arranged on the right side from top to bottom, and the second half is arranged on the left side from bottom to top, and the corresponding numbers on the left and right are connected. This is the form of the first round of confrontation. The number 1 in the second round is fixed, and other numbers are rotated counterclockwise by one place, resulting in a new form of confrontation, and so on, which can not only exclude other forms of confrontation.
For example, there are 8 teams participating in the competition, and the competition order is as follows:
One, two, three, four, five, six and seven rounds.
1-8 1-7 1-6 1-5 1-4 1-3 1-2
2-7 8-6 7-5 6-4 5-3 4-2 3-8
3-6 2-5 8-4 7-6 6-2 5-6 4-7
4-5 3-4 2-3 8-2 7-8 6-2 5-6
If it is team 7, change the number 8 to 0 to represent the team (person) against it.
3. Level determination
Single round robin is ranked by the number of wins. If the number of wins of two teams (people) is equal, the schedule will be arranged according to the relationship between the two teams. If there is an equal number of three or more winners, they will be arranged according to the following terms:
(1) The winning percentage of the team (person) in all competitions in this competition;
(2) The winning percentage of the team (person) in all competitions in this competition;
(3) The winning percentage of the team (person) in all competitions in this competition;
(4) draw lots.
Three. Group single round robin
In the first stage, each team will be divided into groups for single round robin, and then in the second stage, the number of teams (people) with the same name in each group will be ranked in single round robin.
4. Mixed system divides the whole competition into different stages, and adopts single elimination system and single round robin system to determine the ranking.