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NBA Draft Lottery Process: How Do Those Ping Pong Balls Work Anyway?

Have you ever wondered exactly how the NBA Draft Lottery works? You might know there's something about ping pong balls and most people understand that teams with the worst records get more chances to "win". Well today is your lucky day (regardless of what day you are reading this, it is still lucky) because we are going to explain exactly how the NBA Draft Lottery works and what that means for the Phoenix Suns.


The first thing to determine is the order in which the teams finished the season. Seeding is a very important factor in this entire lottery process. What we do is take the records of the team and line them up in reverse order from worst to best of the 14 lottery teams.

Here's that list for 2011 (via SB Nation/NBA) along with the odds that each team will win the lottery and get the first pick or a top three pick. We'll explain that more after the list:

No. 1 Pick Top 3 Pick
Timberwolves 25.0% 64.3%
Cavaliers 19.9% 55.8%
Raptors 15.6% 46.9%
Wizards 11.9% 37.8%
Kings 7.6% 25.4%
Jazz (from Nets) 7.5% 25.3%
Pistons 4.3% 15.0%
Cavaliers (from Clippers) 2.8% 10.0%
Bobcats 1.7% 6.1%
Bucks 1.1% 4.0%
Warriors 0.8% 2.9%
Jazz 0.7% 2.5%
Suns 0.6% 2.2%
Rockets 0.5% 1.8%


Ping pong balls and odds

Now that we have our list, each team is assigned a certain number of 1,000 possible permutations. The team with the worst record gets 250 out of 1000 chances (25%) and so on down the line.

The Suns, slotted at the 13 seed, get six winning permutations.

Once the permutations have been randomly assigned to each team, the ping pong balls can spring into action. 14 of them are put in the jumble machine with each ball having a number printed on it (one through 14). When the time comes on May 17, four balls are drawn and the numbers are arranged to match the permutations given.

For you math geeks, here's a more detailed explanation:

To determine the winner, fourteen ping pong balls numbered 1-14 are placed in a standard lottery machine and four balls are randomly selected from the lot. Just as in most traditional lotteries, the order in which the numbers are drawn is not important. That is, 1-2-3-4 is considered to be the same as 4-3-2-1. So although there is a total of 24 (4!) orders in which the balls numbered 1-2-3-4 can be picked, they are all treated as the same outcome. In doing this, the permutation of 4 balls from 14 becomes the combination of 4 balls from 14. That is, the total of 24,024 (14! / 10!, or 14x13x12x11) possible permutations is reduced by a factor of 24, to 1,001 combinations (or 14! / (10! x 4!)). Of these, 1 outcome is disregarded and 1,000 outcomes are distributed among the 14 non-playoff NBA teams. The combination 11-12-13-14 (in any order that those numbers are drawn) is not assigned and it is ignored if drawn; this has never occurred in practice.    

There are three drawings of the balls. The first determines the first overall pick in the draft, the second drawing the second pick and the third drawing the third pick. The 11 teams not selected are put in order based on the original seeding.

As the 13th seed, the Suns have a .006 chance of "winning the lottery" and getting the number one pick and a .007 and .009 chance of getting the second or third seed. They have a 96 percent chance of end up with the 13th overall draft pick. 

Biggest lottery "upsets"

In the history of the draft lottery going back to 1985, two teams won the first pick when they had less than a two percent chance going in.

The Chicago Bulls in 2008 finished the season with the ninth-worst record (33-49) and had 17 out of 1000 chances to win. They won and they got Derrick Rose. Talk about luck.

In 1993 the Orlando Magic finished with the 11th-worst record and turned a 1.52 chance into the first pick. You might remember a guy named Chris Weber who the Magic traded to Golden State for Penny Hardaway and three future first round picks.

On the flip side, only four teams since 1983 who had the worst record in the league won the lottery and ended up with the first pick: 1988 Clippers (Danny Manning); 1990 Nets (Derrick Coleman); 2003 Cavaliers (LeBron James); 2004 Magic (Dwight Howard).


The NBA Draft Lottery will be held on May 17. Suns fans, cross your fingers but for your sanity's sake, just plan on drafting 13th.