Drafting a “Winner”: Does the NBA Overvalue NCAA Champions in the Draft?

By: Evan Barone

Reading Time: 5 minutes

In the draft, every NBA front office is searching for that edge. While there are relatively tangible attributes that all teams look at to judge a player, such as shooting ability or athletic prowess, talent evaluators often try to look beyond the numbers for an indication that a particular player is destined for greatness. This usually comes in the form of “intangibles,” a player’s overall mindset. One rationale that has been pervasive throughout the NBA community is that X player is going to be great because “he’s just a winner.”

The intangible value of having “a winner’s mindset” is something often discussed when evaluating college prospects. The popular theory is that players who have won the NCAA title have proven through their experience that they can lead a team to success. Heading into the 2015 NBA draft, one of Jahlil Okafor’s perceived strengths was that “he’s proved to be a winner at every level,” which included winning the NCAA championship in his freshman year at Duke.

He and fellow champion Justise Winslow were both taken high in the draft, 3 and 10 respectively, but so far neither has quite panned out in the league. NCAA champion Jalen Brunson was another player lauded for his intangibles heading into the 2018 NBA draft. He was selected to the Mavericks 33rd overall, and in coach Rick Carlisle’s initial press conference on the selection, he made a point that “[Brunson’s] won the national championship two out of the last three years, he’s obviously a winner…the character is obviously there with what he’s been able to do winning two in the last three years.”

Jalen had many of the traits that would dissuade teams from drafting a player. He’s undersized, un-athletic, and old for a prospect, having spent three years at Villanova. Even still, according to Jalen’s former coach Pat Ambrose, “you can’t measure heart and that brain Jalen has. Wherever he has gone, he has been a winner.”

This all sounds nice, and it’s a good talking point to give to fans on draft night, but do NBA teams actually buy into this theory? More specifically, are prospects that have won an NCAA title viewed more favorably by NBA teams, and should they be?

To answer these questions, I used a dataset of all players drafted to the NBA between 1989 (when the draft went to two rounds) and 2007 (so that players who have only played a few years in the league are not included). I then created a dataset of all drafted players during this period who won an NCAA championship. To determine whether or not NBA teams are drafting players who won a championship in college too high, I had to compare the output of each championship player to the expected value of the draft position where they were selected. My calculations were made in career win shares¹ to best reflect the total added value of the player over the course of their career. I averaged all the differences between actual win shares of the championship player and expected win shares for the draft position where they were selected. The results were that, on average, championship players underperform their draft position by approximately two win shares.²

Because the career production of any given player in a draft class varies from year to year, we cannot know the true value of each draft position. Since drafted players who won an NCAA title is a subset of all drafted players, we have to account for variability in both samples.³ Taking this into account, we are 77% confident that college basketball players who won the NCAA championship actually perform worse than the average player at that draft position, with only a 23% chance that this difference is due to sampling variability.⁴ Therefore, it is more likely than not that NBA teams attribute too much value to the “winner’s mindset” when evaluating prospects.

To quantify roughly how much additional value is given to prospects who won the NCAA title, it’s helpful to determine how much an NBA team is overvaluing these players in terms of draft position. Since the calculations or player performance are done in career win shares, we have to estimate the average expected decline in career win shares between draft picks in order to translate the average difference in production from win shares to draft picks.

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In a plot of average win shares per draft position, results show that there is a .73 decline in career win shares between each pick as you go further back in the draft.⁵ Since the results of our testing indicated that NCAA champions underperform their draft stock by two win shares, we can conclude that players who won a college championship are drafted somewhere between two and three picks too high.⁶

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So, why are NBA teams making the mistake of drafting championship winners too high? Why are NBA general managers incorrect to add additional value for act of winning an NCAA championship?

One player alone cannot win a championship. The ability of the rest of the team and the unpredictability of the NCAA tournament have an impact over a team’s chances of success. Still, this is not enough to explain why NBA teams are overvaluing NCAA champions. These guys are usually elite college players contributing heavily to their team. Thus, their performance would likely have a large impact over the outcome of the season. Therefore, if their impact helps the team win the NCAA title, their abilities should be looked upon positively.

This is a logical line of thought, however, when a player wins the title, their contributions are actually over-magnified because of double-counting. NBA general managers are counting abilities plus winning when evaluating these prospects. But to count winning separately is to double count that player’s value, because the amount that a player adds to winning is a result of their abilities on the court. These abilities  are already being accounted for in the evaluation of the player, so winning should not receive any additional weight.

Basically, players who win NCAA championships are typically good players, but their talent should be evaluated based on the merits of their game, not the fact that they won the title. Championship players have been drafted 21st overall on average, which is well above the expected average draft position for all picks between 1989 and 2007 of 29.⁷ In reality, they should be getting drafted closer to 23 or 24 overall, which is still considerably above average. The abilities these players have, abilities that contributed to winning the championship, do make for a valuable prospect. However, the fact remains that these players are being overdrafted relative to their actual skill level, which suggests that NBA front offices are giving unwarranted value to the act of winning alone.

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The value of winning continues to be a talking point in the basketball community. As a result, NBA teams often fail to evaluate these prospects correctly, which can end up in them selecting inferior talent. All front offices want that edge. Unfortunately, there is no secret formula for evaluating prospects. If there was, it most likely would have been found by now. Front offices need to stick to evaluating players based on the merit of their abilities. For those GM’s who look for added value in a “winning mindset,” they have a fundamentally flawed conception of talent evaluation.

 

Footnotes

¹ Win Shares is a stat that calculates a player’s individual contribution to total team wins. Full description in link

² Data taken from basketball-reference.com. Dataset and summary of statistics in link

³ Two sample t-test was used for statistical testing. Complete test in link

⁴ 23% is the probability of Type 1 error. Type 1 error occurs when a premise is incorrectly accepted. This is also known as a “false positive”

⁵ This is not a perfect estimation because the true decline in value of a draft pick appears to be nonlinear. However, a linear estimation of decline is still useful with the goal of roughly estimating a single value to quantify average decline per draft position.

⁶ Average of the all the differences between actual win shares of championship players and the expected win shares for their draft position divided by difference in win shares per draft position equals the difference in expected draft position and actual draft position. -2.03/-.73=2.73 or ≈2-3

⁷ The average draft position across all drafts from 1989-2007 is 29.07. This is because as expansion teams have entered the league the draft has expanded from 54 to 60 picks. The average draft position for championship players of 20.62 is still well below this average. Complete data in link

 

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