Friday, July 31, 2015

How bad could Jordan Spieth's putting be in ANY range?


This year's Open at St. Andrews was by far the most exciting that I have watched.  Forgive me for being a big Zach Johnson supporter - I've been the stat advisor to Zach and his team for the past four years.

Please don't tell Zach, but I was also pulling for Jordan Spieth.  It bothered me to hear the commentators continually refer to Jordan as a poor putter in the important 5-10 ft. range.  I understand that this was intended to build suspense as Jordan stood over these critical putts.  But let's put the record straight.  First, Jordan is by no measure a "poor" putter.  Second, the rationale cited was  Jordan's Tour ranking of #87 in that range, which is just WRONG.  The ranking number is not wrong, but its use to support the assertion is dead wrong.  I decided to write this blog when a good friend (a very knowledgeable golfer - but not a ShotByShot.com subscriber?!) quoted this stat in the context of "... can you believe how bad Jordan is with these short range putts?" I did some homework to set him straight, and realized it was worth sharing.  I hope you agree.

Compaction
First, the Tour maintains a total of 649 Tour Stats.  With the exception of the two Strokes Gained stats (Putting and Tee-to-Green), the remaining 647 stats are one-dimensional snapshots of a small slice of performance and can be very misleading.  The rankings represent where the player stands relative to his peers.  But at this level - the very top of the game - differences are very slight.  I refer to it as "compaction."  For example, let's examine exactly what Jordan's 87th ranking in the 5-10 ft. putt range really means.
  • The #1 ranked player is Troy Merritt (who?) makes 65.15% of his opportunities in this range.
  • Jordan's 57.3% is better than the Tour avg. of 56%.
  • This stat does not drop below 50% for any player until #190
  • The worst player in this range, ranked #196, makes 45% of his opportunities.
  • Like most players, Jordan averaged less that three putts (2.7) in this range per round.
  • Finally, the range should be 6-10.  There is way too much difference in the average make % between 5' 4" and 8 or 9+ ft. so each player's actual spread of distances will influence the result.
Bottom line, Jordan's 57% is not bad at all - he's better than average in a very small slice of the overall putting pie.
Strokes Gained
Jordan Spieth is ranked #6 in this MOST IMPORTANT putting stat.  I don't recall this stat being mentioned in the telecast.  For those that are unfamiliar, this stat compares the player's performance for the distance of each putt opportunity to a model of the average performance of the entire Tour for that distance.  It is as close to perfect as a golf stat can get.  For a more complete explanation see:
 How Good is Strokes Gained Putting

The graph above displays Jordan's current Tour rankings from each distance range.  For perspective, I added his Strokes Gained Putting ranking (6) in blue.  When I average all the Tour rankings by range, Jordan would rank #48.  This makes no sense as the vast majority of putts fall into the first three ranges.  So I performed a weighted average based upon my educated estimates of the # of putts within each range.  In theory, the weighted average should approximate Jordan's overall skill level.  Instead it bumps Jordan up to #64 - a long way from his real skill level - #6.

In closing, my plea to broadcasters:  If you are going to cite statistics, please understand what they really mean.  If you need help, call me!