How does a holes handicap correlate with the holes difficulty?

While it is widely believed that the hole handicap is a measure of a holes difficulty this is not strictly correct according to the USGA.

The USGA states “The stroke hole allocation (hole handicap) should not be based on the difficulty of a hole, but rather where players with higher handicaps need strokes in order to obtain a half in match play. ”

So even with this explanation from the USGA most players would agree that often the #1 handicap hole on a course is perceived to be one of the easiest holes and the #18 handicap hole is often times one of the easiest holes on the course to par.

In order to see just how right or wrong this belief that hole handicap = difficulty I have taken the scores from roughly 27,000 scores logged on Golfingstat.com and graphed the average (mean) score relative to par (e.g. birdie = -1, par = 0, etc.) against the hole handicap number.

handicap_vs_average_score

Here is the table to support that graph:

hole_handicap_table

 

 

 

 

 

 

 

 

 

 

As you can see in the table and graph the holes with the lowest 4 handicap numbers (#1 through #4) are significantly more difficult than the average hole. Also the holes with the highest 4 handicap numbers (#15 through #18) are significantly easier than the average hole. So just looking at these 8 holes it seems that the belief that the hole handicap number is a good measure of the hole difficulty holds up.

The middle 10 handicap holes do not really seem to be as closely mapped to their actual difficulty as they have some weird anomalies such as #11 being on average significantly more difficult than #12.

Golf Score Predictor

I have not added functionality in a long time but last week I decided now was the time! I added a feature to the stats menu called “Projected Scores”. Basically this takes your handicap and estimates what you will shoot based on the course and tee. It provides five estimates:

  • Real Bad (-20%)
  • Bad (-10%)
  • Expected
  • Good (+10%)
  • Real Good (+20%)

The expected number is based on your handicap. If you were to shoot your handicap then that would be the score that you should put up. The +/- numbers are a percentage above or below your handicap. The USGA has a cool little table that helps identify a sandbagger based on the odds of you shooting +/- your handicap. (http://www.usga.org/handicapping/articles_resources/Odds-of-an-Exceptional-Tournament-Score/)

Using that table and using me as an example and Royal Ontario Blue Tees as the course/tee:

Handicap: 21
Good: 95 (-3 of my handicap)
Real Good: 92 (-5 of my handicap)

So the odds of me actually shooting these scores are as follow:

Good: 21 to 1
Real Good: 174 to 1

This really puts things into perspective in terms of how hard it is to improve drastically and how golf is a game of small gains.

5 Handicap vs. 20 Handicap

I went through the exercise of comparing a 5 handicapper to a 20 handicapper. The first thing that jumps out is the number of rounds that a 5 handicapper is playing.  In this comparison the 5 handicapper has played 26 rounds over a 2 month period while the 20 handicapper has played only 4. If you are going to get better you need to practice and play more.

Putting (2.5 strokes)
33.5 putts per round vs 36 putts per round

You always read that improving your putting can drastically lower your score. In this comparison the 5 handicapper putts on average 2.5 putts less a round than the 20 handicapper. While I am sure everyone would like to shave 2 or 3 strokes off their round but this isn’t a massive difference.

Iron Play and Chipping (17.3 strokes)
To get a sense of the importance of iron play we are going to look the holes where drivers do not factor in (Par 3’s). Our 5 handicapper averages 3.4 strokes per par 3 while our 20 handicapper averages 4.5 strokes per par 3. If we take that average and apply it to a whole round (18 holes) that is 61.2 for the 5 handicapper and 81 for the 20 handicapper. Now we take the putts off of this and it becomes 27.7 and 45 respectivly. This is a difference of 17.3 strokes.

This also explains the large difference in greens in regulation (50.45% vs 12.5%). If you hit better approach shots you will hit more greens in regulation.

Driving (1.8 strokes)
To assess driving we are going to look at par 4s then take away the expected number of iron strokes and putting strokes (par3 averages).  The 5 handicapper averages 4.45 on par 4s and the 20 handicapper averages 5.65 on par 4s. The average over 18 holes for the 5 handicapper is 61.2, while the average over 18 holes for the 20 handicapper is 101.7. If we take the iron strokes from “Iron Play and Chipping” out of this we end up with 18.9 for the 5 handicapper and 20.7 for the 20 handicapper. This means that driving only accounts for roughly 1.8 of the strokes per round.

Driving clearly has an impact on iron play and chipping stats as well. If a player hits a long and accurate drive then more often than not they will have a shorter iron with a good lie for their approach shot.

Interestingly even though there was not a large difference in the par 4 stats (with par 3 taken out) there was a slight difference in the fairway %.  The 5 handicapper hit 64.1% of fairways while the 20 handicapper hit 47.25% of fairways.

So to recap it appears that iron play and chipping is the biggest difference between a 20 handicapper and a 5 handicapper.

Links:
Golf Handicap Tracker
5 handicapper (my dad)
20 handicapper  (me)