1, Coin Toss and Territory Signing
Since the establishment of the NBA league, the draft has become a very important part of the league. But in the early days of NBA, the determination of draft picks was known for being simple and crude.
At that time, there was no so-called lottery draw. The team with the worst record would get the No. 1 pick that year, the team with the second worst record would get the No. 2 pick, and so on. In this way, after the regular season ends that year, each team's draft picks have been determined. If two teams have the same record, a coin toss will be required to determine whose draft pick is higher.
In addition to the simple and crude coin toss, in the early days of the NBA, there was something called territorial signing. That is, a team can identify potential rising stars from universities in the team's area before the draft. Since 1949, a total of 22 people have been signed through the territory, including Hall of Fame players such as Wilt Chamberlain, Tom Heinsohn , and "Big O" Oscar Robertson .
However, this simple and crude method has great disadvantages. Many teams started to mess around in order to get good picks. Finally in 1966, the NBA decided to make adjustments. The team with the worst record no longer automatically won the No. 1 pick. Instead, the two worst teams in the East and West determined the No. 1 pick by tossing a coin. At the same time, territorial visas were also abolished that year. This is the prototype of the NBA lottery. To a certain extent, it can reduce the probability of a bad team to a certain extent. However, judging from the overall rules, teams with relatively poor records still have a high probability of obtaining high draft picks. Therefore, the problem of bad display has not been completely solved.
2, Frozen envelope
In 1984, two major events happened in the NBA. One was that Michael Jordan entered the league, and the other major event was that David Stern became the NBA president. In the more than 30 years since then, the NBA has developed rapidly and has now become one of the most mature sports leagues in the world. It has to be said that both Jordan and Stern have greatly promoted the development of the NBA.
After Stern came to power, he made great reforms to the lottery drawing system. In the 1985 lottery drawing ceremony, Stern overturned all previous lottery systems. He put the names of all teams participating in the lottery draft into the same envelope, and then drew the No. 1 pick, the No. 2 pick, and the No. 3 pick until the envelopes were completely drawn. This also means that all teams in the lottery area have an equal probability of winning the No. 1 pick.
From the current point of view, this is not a reasonable lottery model, and many people even think that Stern made such a reform for the purpose of conducting secret operations. Someone once broke the news that David Stern would put team-specific envelopes in the refrigerator before the draft. He was then able to distinguish through temperature perception and thus take out the envelope of the team he wanted to take out.
During those years, conspiracy theories have been lingering over the NBA, and Stern was also pressured to change the rules of the NBA lottery again in 1987. The specific method is still to draw envelopes, but the lottery only takes place for three rounds to confirm the ownership of the top pick, second pick and lottery pick. Such a change is undoubtedly a boon to teams with relatively poor records, because the teams with the worst records have the worst luck and can draw the fourth pick.
3, Table Tennis that Changed Destiny
In 1990, David Stern carried out another reform of the lottery. He introduced the concept of table tennis into the lottery and adopted the method of permutations and combinations, which reduced the maximum number of pitfalls. Human factors interfere with the draw, and fairness is greatly guaranteed.
Since then, people have called the ping pong balls used in the lottery "the fate-changing ping pong balls" because the quality of the draft picks has all depended on luck, and the team that gets the high pick has , it is very likely that the revival will be completed in a short period of time.
Initially, teams that did not enter the playoffs were given different numbers of ping pong balls according to their records. The team with the best record received 1, the second best received 2, and so on. In this way, teams that did not enter the playoffs that year The 11 teams in the post-match produced a total of 66 table tennis balls. These table tennis balls were put into a machine selection container at the same time, and the top pick, second pick, and third pick were randomly drawn from it. The remaining 8 teams were ranked in order according to their records. Bit.
However, this model also has drawbacks, that is, the team with the worst record has a 16.7% probability of winning the No. 1 pick, while the probability of the team with the best record in the lottery winning the No. 1 pick is also 1.5%, and the gap is not that big. . Therefore, after 1993, the NBA continued to reform, further increasing the probability of the teams with the best and worst records winning the No. 1 pick. After the reform of
, there are still 14 table tennis balls placed in the lottery container. Each ball is marked with a number from 1 to 14. Each time the lottery is drawn, 4 are drawn out to form a numerical sequence. The team corresponding to the serial number is considered the winner. Before the lottery, the NBA allocates 1,000 sets of number sequences to lottery teams in proportion. The team with the worst record in the lottery zone can have 250 sets of numbers, while the team with the best record in the lottery zone can have 50 sets of numbers. . That is, the team with the worst record has a 25% chance of winning the No. 1 pick, and the team with the best record has a 0.5% chance of winning the No. 1 pick. At the same time, the lowest pick available to the team with the worst record in the lottery is still the fourth pick.
4, current situation
In September 2017, the NBA announced the latest lottery reform plan. The specific content is divided into two parts: First, the probability of the three teams with the worst records winning the No. 1 pick will become 14%, and the probability of the remaining teams winning the No. 1 pick will also decrease in turn. Approximately 1%-2% reduction. Second, the number of draft picks determined by the lottery has been increased from the previous three to four. From then on, the worst outcome for the team with the worst record is the No. 5 pick, the second-worst team gets the No. 6 pick, and so on. The purpose of changes like
is to put an end to the increasingly obvious phenomenon of ruining and further enhance the enjoyment of the NBA.
Finally, is attached with the probability of drawing lots for each lottery team this year!
