Are the top golfers in the world affected by the quality of their company? Do they lift their performance when they're paired with great players? You wouldn't immediately think so. After all, no golfer reaches the highest levels of the profession without having learned how to block out distractions and simply play the course. But a look at the data suggests otherwise: The best golfers do play better when they're teeing off against their fellow elites.

The following table shows how golf's top players performed when paired with or without another player with a World Golf Ranking in the top five. The results are from PGA Tour events during the 2013 season. Match-play events and tournaments with smaller fields (e.g., the WGC-Accenture Match Play Championship, the TOUR Championship and the President Cup) are excluded from these numbers.


Through two rounds of a given PGA Tour event last year, a professional golfer ranked fifth or better was over 70 percent more likely to be among the top 20 on the leaderboard if he had drawn a pairing with another player ranked in the top five. This difference is very significant, both practically and mathematically. Assuming the results of top-five players as shown above are nearly normally distributed, there is only a 0.3 percent chance of achieving such an extreme outcome (in either direction) if playing partners had absolutely no effect on performance.

The number of instances in which top-five golfers missed the cut in 2013 was rather small, so although they were over four times more likely to miss the cut when paired with someone outside the top five, it is difficult to definitively draw conclusions on that particular statistic. That said, when coupled with the rest of the data in the table above, there does appear to be a correlation.

Note that the manner in which many of the initial pairings are drawn on the PGA Tour is not randomized. Tournaments generally group players with similar rankings during the first two rounds. Because of this, it would be difficult to compare, say, the second-ranked golfer's grouping and that of the 22nd-ranked player, who typically will be paired with lower-ranked opponents.


For example, top-five players were paired with at least one other golfer ranked among the top five roughly 45 percent of the time during the opening two rountds of a PGA Tour event in 2013. This was true for fewer than 10 percent of the groupings involving players ranked between No. 21 and No. 25, and that number drops below 2 percent for golfers between No. 51 and No. 55.

For that reason, along with the fact that higher-ranked players generally score better than lower-ranked ones independent of their playing partners' ability, we have to focus on such a tight range of players when considering this data. By reviewing statistics from golfers ranked within five spots of each other at once, it increases the likelihood that their playing partners are more comparable and, thus, that the data are more meaningful.


And the trend is similar within other spreads, as well. Pros ranked between No. 21 and No. 25 were over 30 percent more likely to be in 20th position or better after two rounds— and over 65 percent more likely to be in the top 10 on the leaderboard (29.8 percent to 17.9 percent)—when playing in a group with at least one other golfer in the top 25.

To further reduce the number of variables that potentially could affect a player's score, the statistics above are based solely on the first two rounds of an event. As tournaments progress through the weekend, golfers are faced with additional factors that may influence their scores. Pressure can increase for those who are still in contention on Sunday. Strategies may be altered late in a tournament as players measure the risk and reward of playing aggressively from ahead or slightly behind. Golfers who have fallen far off the lead may be more likely to lose focus than someone near the top of the leaderboard.


Can we discern anything on an individual level? The following is how golfers fared when grouped with certain top-five players:

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PlayerOpponent in Leaderboard Top 10 through 36 holesOpponent in Leaderboard Top 20 through 36 holesTop-5 opponent in Leaderboard Top 10 through 36 holes

The once-popular notion that Tiger was an intimidating force whose mere presence blew people off the course, however true or fanciful it was in his prime, was clearly no longer the case by 2013. (Granted, our numbers here don't include the final round.) For whatever reason, Mickelson, by a long shot, is much more difficult to play with than anyone else—top 5 golfers who played with Mickelson were among the Top 20 of a leader board heading into the weekend roughly half as frequently as they were in any other pairing.


Golf is a sport that loves its own mythology, and as such, it's been barnacled with all manner of empty aphorism over its long years. But at least so far as can be observed here, there's truth to one: In some not-small part, the game is played in those five inches between your ears.

Eric Eisenberg is a freelance writer. You can follow him on Twitter here, and his blog, (n)umericSports, here.