A popular sports radio host says “if you take the time to email me, I’ll take the time to read it.” The same goes for me. Of course, he probably gets tens of thousands more emails than me. Still, I do read and think about the emails I receive, and I encourage you to send me more. Our email addresses can be found on the staff page.
Over the past few weeks, two emails in particular have inquired about The 40-30-20-10 Rule. Recently, I applied the rule to the LPGA and to the Champions Tour. Both emails posed questions or suggestions that I thought I’d answer here.
Email Number One: Will
I took a look at your spreadsheet, and experimented with the data. I think there’s a problem. I can illustrate it by changing your rule to 10-30-20-40, exchanging GIR and DA. If you plot those results, you get a similar correlation. In fact, you will get similar correlations with any percentages you choose.
Your idea likely has merit, but you aren’t applying the data in a meaningful way. I will experiment a bit more tonight, and see if there’s a better method.
It’s an interesting thought. I ran through an assortment of variations of the 40-30-20-10 rule and shifted weight in different directions. Ultimately, what led me to the way the rule is weighted now is the research I did on the correlation of each statistic to scoring and earnings. No matter the tour or year, it always fell in this order of correlation, strongest on the top and weakest on the bottom:
- Greens in Regulation (GIR)
- Putting
- Driving Distance (DD)
- Driving Accuracy (DA)
Probably the only exception to the general rule is DA, which has gone from strong to weak in correlation over the past 20 years or so. Still, we are talking about the game as it is today… and today it is greens and putting.
To better represent (and validate) the research I’ve done, I wanted to show Will and everyone the difference between what Will suggested and the 40-30-20-10 rule as it is today. Since I had the Champions Tour data handy from last week, I thought that I’d just flop the GIR and DA and plot the same graphs.
Here’s Will’s graph:
And here is the graph from last week:
I can see why Will and others would think that the first graph is not that much different than the normal 40-30-20-10 rule graph. The slope of the graph is similar, but the difference is in the proximity of the points to the line. This is represented in the RSquare value to which I’ve previously referred. The RSquare value is a measure of how tightly a line fits the points, or a statistical term which tells you how good one set of data can predict the other. An RSquare value of 1.0 means that you can perfectly predict the outcome of one value using the other.
For Will’s graph, the RSquare value is 0.6057. This really isn’t too bad, but using the normal 40-30-20-10 rule, the RSquare value jumps to over 0.85, a significant increase. The slope of the line may give us a trend, but the definitive proof for which equation better correlates the data is in the RSquare value… and in the end, when GIR is 40% and DA is 10%, the correlation is much stronger.
Email Number Two: Jay
Haven’t you just discovered that scoring average is the most important statistic? If you multiply GIR * Putting Average you basically get a player’s score – which correlates very well with money. I understand that missed greens aren’t included but when you add in total putts, that gives you a pretty good proxy for up and downs.
In fact, the more greens hit the closer the approximation to scoring average your 40 and 30 percenters get.
As Bobby Jones once said – golf is turning 3 into 2. The best way to do that is a GIR and birdie putt (i.e. lower putting average).
Of course scoring average is the most important statistic. If you hit the most greens, had the best putting average, and hit the ball great off the tee but didn’t score well, you wouldn’t make very much money in professional golf. The point to the 40-30-20-10 rule is to predict scoring average and earnings by virtue of the different facets of the game. Just correlating score to earnings wouldn’t have much meaning to me or anyone else.
I’m a bit lost when Jay talks about multiplying GIR * PA to get a player’s score. Let’s take Phil Mickelson:
70.7 * 1.703 = 120.4
That’s not very close to Phil’s scoring average, and variations of that ((0.707 * 18) * 1.703, etc) fail to come close as well. I even tried using the rankings for each stat (40% of GIR, 15% of PA and 15% of PPR), but that too failed. I asked Jay to shed some light on this and he replied with this:
Say I hit 100% of GIR and my putting average per GIR was 1.66 that would mean that I birdied 33% of the holes I played or said another way I had (.66 * 18 = 12) pars and (.33 * 18 = 6) birdies. You have just computed my score: 66 on a par 72 course.
Now, we don’t usually hit 100% GIR. On the other holes, total putts taken is pretty good proxy for how often I got up and down that day (ie saved par). For instance, total putts under 30 might correlate with a scrambling percentage of 70%. Scrambling percentage can be used to calculate your score on the greens you missed.
For the most part, this is true. The only caveat is when players get up and down for a bogey or worse after a penalty shot. I’m still intrigued by using some sort of formula to get to score by using total putts as, in Jay’s words, a proxy for the greens not hit. The hope would be that the “worse than bogey” scores would smooth out over all players.
I do agree with Jay on one thing, and that’s his quote from Bobby Jones. I had never heard it before and found that the exact quote is “The secret of golf is turning three shots into two.” Golf is about hitting your spots… or greens, and then taking advantage when you do it. I’ve been in a funk lately and am having a tough time making birdie putts. I’m hitting my normal amount of greens, but my putting average is up to nearly 1.9. That means I’m only making one or two birdies per round.
This quote is even the title of a book written by Bill Moretti on the short game. While Moretti focuses on the short game, which is very important, remember that you probably won’t make a two without getting on or near the green.
Thanks Guys
I appreciate both Will and Jay’s input. I’m hoping to hear back from them and from others about ideas and questions on not only the 40-30-20-10 rule but other number-related topics as well. I’m going to try and make this a regular drop-in column when some interesting thoughts come up from our readers. Don’t be shy and drop me an email, especially if you disagree.
After reading the above article, I am not sold on the importance of the 40-30-20-10 rule.
The rule seems to be stating the obvious.
1) Driving distance does not equal score
2) Driving Accuracy means less today and means less than putting
3) Putting means less to score than greens in regulation
Lower scores means more money.
It would be interesting to see how the same player fares in scoring from 100 yards, 110 yards, 120 yards, through 250 yards from a Par 4 pin and see the average score from those locations. You could create 2 categories for these scores (rough and fairway).
This analysis would indicate how much better a player would score if he/she could hit the ball 10 more yards and where that benefit would be the greatest. Some players may have some scoring aberrations.
You could then analyze (from a scoring perspective) the benefit to the score from the fairway versus the rough.
I think you would need multiple years for players to have some real significance to the stats (sorry).
I would guesstimate that the added 10 yards is important to score and is what pushes some players to the top. I would also guesstimate that being in the fairway versus the rough for some players is what pushes them to the top.
Andy,
What may be obvious to you and me, is not to others. There are slews of people out there that, if you listen to them, believe that length off the tee is the sole and determining factor in scoring.
Even if it is obvious, what I’m attempting to do is put some weight into these assumptions and beliefs. I have yet to see someone try and put some numbers behind these categories. The importance is in the weight…
Your other thoughts are interesting and like you alluded would be hard to compilate. I’m unfortunately bound by what statistics are available.
Dave,
Sorry I didn’t get back to you, I haven’t had time to study this yet. Your points re my email are well taken, and I appreciate that you’re trying to establish a correlation that might actually have some value to golfers. There’s certainly years of data available; maybe you could become the Bill James of golf. 🙂
Just wanted to pop in to acknowledge your post, I don’t have anything constructive to add at this time. I will say that looking at the rsquare function made my head hurt, I’m more comfortable using correl(). The results seem relatively similar, anyway.
btw, I think those functions depend on real numbers or references in the data. I notice in your spreadsheet that the B column, or x-axis, contains text (like T7, tied 7th). I thought your rsquare values were a little high, did you account for that?
Andy,
Have you seen Dave Pelz’s statistical work in the Short Game Bible? He makes a very convincing, data based argument that wedge play or closest to the pin from 100 yds and in is the most important factor in determining success on the tour.
Why? Because being better than others at getting close to the pin from 7-4 iron distance does not mean much. Even if a player gets a higher percentage of his mid-range shots closer to the pin than competitors it doesn’t matter. Because even the best touring pros seldom get a shot beyond 100 yards from the pin close enough to make the next shot (a putt) the last.
Being more accurate than others at 125-225 yards still results in two more strokes whether the player gets mid-iron shots 12 feet or 25 feet from the hole on average. Ninety-five percent of the time both competitors take two puts to finish the hole.
Plez did not find much colleration between driving distance or putting skill to money won on tour. What really matters is when the player misses the green. How often does he get up and down? Players who can consistently get full wedges, partial wedges and pitches within 10 feet of the pin convert their next shot into the last shot much more often than those who cannot.
Touring pros only hit the green in regulation about 65 percent of the time or in other words, the best players in the world only hit around 12 greens in regulation. That leaves 6 greens where the best players in the world have to try to get “up and down”. It makes perfect sense to me that those who get their wedges consistently closer to the pin than others win a lot more money.