NFL Scouting Combine Not A Good Predictor of Draft Pick Success

Every April, general managers and head coaches fear that their NFL Draft selection of "can't miss" college players may end up being added to the long list of past multi-million dollar draft mistakes.
So, for last month's NFL Draft, they hope they found the right matrix of information that will reveal those players with true NFL potential. One set of criteria that seems to get more media attention every year is the scouting combine, a collection of physical and mental tests given to about 300 invited prospects.

However, university researchers have now shown the tests are not good predictors of success in the NFL.

According to ESPN, of the top 10 player selections in the last five drafts (50 players total), eight have been released or traded at least once and five are completely out of the league.

Teams are becoming less willing to gamble millions of dollars on a player who has not played a single snap in the league.

The combine event, held in Indianapolis each February, was meant to provide some common denominators to compare players. Physical tests such as the 40-yard dash, shuttle and agility runs, bench press, and the vertical jump are combined with the Wonderlic Personnel Test (WPT), a 50-question general intelligence test, to paint a profile of a player beyond his on-field resume.

Of course, teams should evaluate the whole package of game film, interviews and position-specific drills, but the combine data seems to be growing in influence. A player's stock seems to rise and fall with their performance at Indianapolis.

In fact, a 2003 Arizona State University study showed that performance at the combine was directly related to draft order, which might indicate that teams rely on these tests more than they admit.

Specific combine tests also seem to make a difference in getting drafted. Last year, University of North Carolina researchers found that there were significant performance differences between drafted and non-drafted skill players in the 40-yeard dash, the shuttle runs and the vertical jump, while drafted linemen performed better in the 40-yard dash and bench press.

But in a new study, Frank Kuzmits and Arthur Adams, professors at the University of Louisville, evaluated more than 300 quarterbacks, running backs and wide receivers drafted over six seasons from 1999-2004.

They compared the players' combine performance on seven physical tests and the WPT with measures of success in the NFL. These three skill positions were chosen as they have distinct performance statistics that can be tracked (as opposed to linemen or defensive players.)

Each position used the success metrics of draft order, salaries for years 1-3 and games played for years 1-3. In addition, QB rating, yards per carry and yards per reception were measured for quarterbacks, running backs and wide receivers, respectively.

No significant link was found between combine performance and NFL success, except between 40-yard dash times and running backs. Interestingly, even the Wonderlic aptitude test did not predict NFL achievement, even though a skill position like quarterback requires a decent amount of cognitive talent. That's not to say other psychological tests would be worthless. Kuzmits and Adams cite other studies that show a player's level of self-confidence and anxiety management to be strong clues to their future accomplishments.

Of course, not all draft picks are surrounded by great teammates and some don't even get out on the field during those first few seasons. But this research showed that good or bad performance in the combine is not related to good or bad performance on the field. So, the researchers question the value of these combine tests as a draft decision support tool.

They do see a similarity between NFL teams choosing players and companies choosing employees.
"Contemporary human resource techniques could be applied to any hiring decision, including the NFL hiring process," Kuzmits told LiveScience. "Basically, teams could develop a regression equation with various success predictors weighted (college success, combine tests and interviews, awards, psychological profile, etc.). It could be done but in the end 'art' would probably trump 'science.'"

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NBA Teams Win With Ethnic Diversity

When the National Basketball Association Conference Finals tip off later this week, four teams will test their level of cooperation, unselfishness and teamwork. One issue that apparently will not get in their way is diversity.

Two new studies have shown that an NBA team's level of racial or ethnic diversity does not have any significant impact on its winning percentage or its players' split-second decision making on the court. These reassuring findings on player unity contrast with a 2007 report showing same-race bias among NBA referees when making foul calls.

The demographics of the NBA have changed dramatically over the last 40 years. African-Americans make up about 76 percent of the league's players, while Latinos and Asians account for three and one percent, respectively. According to the NBA, 77 international players from 32 countries contributed just over 17 percent to team rosters. There are not only potential ethnic and cultural barriers, but also language differences that may impact a team's chemistry.

For any organization, results matter. However, few groups of co-workers have their teamwork watched, measured and analyzed to the extent of an NBA team.

Diversity measured 
Paul Sommers and Jessica Weiss of Middlebury College wanted to see if the level of an NBA team's diversity affected its ability to win. For the last three complete NBA seasons (through 2007-08), players who had at least 800 minutes of court time were divided into one of five racial or demographic groups; African-Americans, Caucasians, East Europeans, Asians, and other foreign-born players who did not play either high school or college basketball in the United States. Using the Herfindahl-Hirschman index (HHI) to measure diversity, a number was assigned to each team for each season. An index of 1.0 would indicate a completely homogeneous team, while more diverse teams would score lower (between 0 and 1).

When the HHI was regressed against each team's regular season winning percentage, no significant correlation was found. In other words, a team's diversity did not help or hurt their success on the court. As supporting evidence, the last three NBA champions, the Boston Celtics (2007-08), the San Antonio Spurs (2006-07), and the Miami Heat (2005-06), had dramatically different HHIs of 1.0, .360, and .781, respectively.

What about that language barrier? If communications suffered, then there should be passing mixups and team turnovers should rise. To find out, Sommers and Weiss divided the teams into two groups, more diverse and less diverse at the median HHI for the league. Over the three seasons, there was no significant difference in total turnovers between the two groups.

The findings were detailed in last month's Atlantic Economic Journal.

Carrying that on-court cooperation theme even further, Brigham Young researchers searched for same-race bias in NBA players when passing to their teammates. To put it bluntly, would a white player subconsciously prefer to pass to another white player if given a choice and, conversely, a black player to a black player? In an exhaustive study, Joseph Price, Lars John Lefgren and Henry Tappen dug into six seasons of NBA data to look at every assisted basket and recorded the race (noted simply as "black" or "not black") of the passer and the scorer. They also noted the other three players on the floor when the basket was made. Of course, there were numerous decision variables that the researchers had to eliminate to isolate just racial preference.

The conclusion: No same-race bias was found in the passing patterns of NBA players.  Study details are available from the Social Science Research Network as part of their working paper series.

Referees don't play fair
Joseph Price is known for his controversial paper in 2007 that concluded there is significant same-race bias shown by NBA referees. In that study, more than 600,000 officiating calls over 13 seasons were analyzed to see if white referees would call fewer fouls on white players than black players and vice versa (black referees whistling black players).

They concluded that the difference was "large enough that the probability of a team winning is noticeably affected by the racial composition of the refereeing crew assigned to the game.”

In fact, their data showed that players earned up to 4 percent fewer fouls and scored up to 2.5 percent more points on nights in which their race matches that of the refereeing crew. From a team perspective, the bias factor may change the outcome of two games out of an 82 game season. For some teams, that may be the difference that keeps them out of the playoffs.

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Tiger's Brain Is Bigger Than Ours

As Tiger Woods heads to Sawgrass for The Players Championship this weekend, mortal golfers wonder what's inside his head that keeps him winning. Well, chances are his brain actually has more gray matter than the average weekend duffer.

Researchers at the University of Zurich have found that expert golfers have a higher volume of the gray-colored, closely packed neuron cell bodies that are known to be involved with muscle control. The good news is that, like Tiger, golfers who start young and commit to years of practice can also grow their brains while their handicaps shrink.

Executing a good golf swing consistently is one of the hardest sport skills to master. Coordinating all of the moving body parts with the right timing requires a brain that has learned from many trial and error repetitions.

In fact, past studies have shown that the number of hours spent practicing is directly related to a golfer's handicap (a calculated number that represents recent playing ability).

Magic number
K. Anders Ericsson, a Florida State professor and the "expert on experts," has spent more than 25 years studying what it takes to become elite in any field, including sports.

The magic number that keeps recurring in Ericsson's studies is 10,000 hours of deliberate practice. If someone is willing to dedicate this amount of structured time on any skill, he has the potential to rise to the top.

Some critics argue that practice is good, but we all start with different levels of innate abilities that put some at an early advantage (i.e. the boy who is six feet tall in fourth grade) While that may be true, Ericsson does not want the rest of us to use that as an excuse. "The traditional assumption is that people come into a professional domain, have similar experiences, and the only thing that's different is their innate abilities," he said in an interview with Fast Company. "There's little evidence to support this. With the exception of some sports, no characteristic of the brain or body constrains an individual from reaching an expert level."

So, what happens to the brain after all of that practice?

In the new study, a team led by neuropsychologist Lutz Jäncke compared the brain images of 40 men divided into four groups based on their experience as golfers. They recruited ten professional golfers (with handicaps of 0), ten advanced golfers (handicaps between 1 and 14), ten average golfers (handicaps between 15 and 36) and ten volunteers who had never played golf (not even mini-golf!).

Interviews revealed the "practice makes perfect" correlation between hours of practice and lower handicaps.

Brain scans (functional Magnetic Resonance Imaging (fMRI) showed that, indeed, there were structural differences, but not in the linear pattern they imagined. While significant differences existed in total volume of gray matter between the pros and the non-players, there was little difference between the pro and the advanced groups or between the average and non-players groups.

When the researchers combined the pros and the advanced golfers into one group called "expert," and the average and non-players into a second group called "novice," a clear dividing line emerged, showing that practice produces a noticeable step up in the brain's gray matter. This jump comes somewhere between 800-3,000 practice hours.

The results were detailed last month in the online journal PLoS ONE.

Step 1: Grow the brain
Another interesting twist is that the pros reported practicing five to eight times more than the advanced group, while the advanced group practiced only twice as much as the average group.

Yet the big jump in gray matter came after golfers achieved a skill level below a 15 handicap, moving from average to advanced. This is consistent with another study in 2008 that measured gray matter volume in students learning to juggle three balls. After learning to juggle for the first time, their gray matter increased. However, once that initial concept was learned, more advanced juggling tricks did not grow more brain cells.

It's been a long time since Tiger's handicap was 15, so clearly the additional years of practice were necessary to reach the top.  And, all of that gray has produced a lot of green.

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