ShotLink Data Article by Dave Pelz

[iacas]

I read an interesting article that shows how golfers of any handicap range can improve by comparing ShotLink data from the pros to ShotLink data collected at the World Amateur Handicap Championship.

Most of the data is pretty common sense stuff. The only thing that surprised me is this:

10 handicappers make twice as many putts from 15' to 20' as scratch golfers (that they make half as many as PGA Tour pros is not surprising). The 20 handicappers make those putts 17% of the time!!! I wonder if that's because they're more likely to be putting in that range for par (or bogey) than birdie (many people are better par/bogey putters than birdie putters). Or maybe because scratch golfers tend to die those kinds of putts at the hole more than the 10 handicappers. Or maybe scratch golfers rea just bad mid-range putters.

Thoughts (on not just the putting, but the article as a whole)???

[hurley9192]

I saw it...good article, but there were a few where the pattern was weird and that was one of them. There was also one with putts/green or something where the scratch golfers were worse than the 20 handicaps. Don't know, but maybe there were only a couple scratch golfers and they had a bad day and the 20 handicaps had a better day. Didn't make sense. The article as a whole gives a good view on the important scoring issues to track.

[iacas]

I saw it...good article, but there were a few where the pattern was weird and that was one of them. There was also one with putts/green or something where the scratch golfers were worse than the 20 handicaps. Don't know, but maybe there were only a couple scratch golfers and they had a bad day and the 20 handicaps had a better day. Didn't make sense. The article as a whole gives a good view on the important scoring issues to track.

C'mon now... I doubt it:

Number of golfers tested: 314 Number of swings measured: 7,278

Dave Pelz, if nothing else, knows how to get a statistically significant number of occurrences. He's not the type to claim a 50% success ratio for something that happens once in two tries.

The article is in the magazine as well, of course, which I just got today so I'll have to give that a good reading as well.

[lamebums]

I read an

I read that article in the magazine just yesterday, I think. It's interesting, and makes several good points, but I still don't think 314 golfers is enough, especially considering the range of handicaps. There's a really big margin for error, there. (Compare it to political polls which ask at least a thousand people on average, with still 3 or 4 percentage points of error.)

That aside, assuming Dave is right on the money for a minute, I'd wager it's because lower-handicap golfers may spend more time looking at the putt, and analyzing it. Analyzing a putt, at least in my opinion, is just finding out ways you can miss the putt, rather than a way you can make it. A high-handicapper might care less, just take one look at the hole and go, and have a whack at it. I think it's all mental, though. (He's right on the money in other places, such as par 3s, hitting irons off the toe, and especially sand play.)

[Shindig]

I read an

I liked the article, and I think your explanation is right on. I have far fewer birdies than my GIRs should indicate, even my close GIRs. However, I do manage to sink some long ones for par or bogey (or worse), but give me the same shot under the same conditions for birdie, and chances are I won't sink it. I absolutely love Pelz's ability to analyze the data. I wish the first book of his that I read didn't read like an infomercial for his products. But his knowledge and data gathering - IIRC, he has degrees in physics and math - are top notch.

[Silvertree]

It's interesting, and makes several good points, but I still don't think 314 golfers is enough, especially considering the range of handicaps. There's a really big margin for error, there.

314 golfers overall is a big enough sample for statistical power purposes. Normally if you are trying to make generalizations of a large population, 100 is considered OK, if just that, and over 200 is good. I personally would want more people then 75 per group (assuming he had equal group size) if possible but I have read many top tier published journal articles that had similar composition.

(Compare it to political polls which ask at least a thousand people on average, with still 3 or 4 percentage points of error.)

Please don't confuse political polls with scientific research.

I doubt that Shotlink lasers introduce nearly as much error as a poll, even including human error. And political polling error is reported as +/- so you have to keep in mind you are viewing a range.

[Leek]

I read the article and I wonder if there were some misprints, typos or editing errors.

[$2 Nassau]

Personally, I am very tentative with birdie putts...especially a 15-20 footer...almost like I don't really care if I make it, just want to make sure I get out of there with a par, because par is a fantastic score for me on any hole(basically a bogey golfer as you can see). I leave birdie putts short usually, you should see me in the rare occasion when I have an eagle putt. Shaking like a leaf.

I seriously doubt a low handicapper/scratch golfer thinks that way.

Back to the point, when it comes time to putt for bogey from 15-20 feet, I'm getting aggressive, because I do not want ANOTHER DOUBLE BOGEY on my scorecard....so yeah...I'm making a strong run at the hole, definitely getting the ball there and giving it a chance to go in. Thing is, when I miss I'm 5 feet past the hole. How often do low handicappers/scratch golfers have a 15-20 footer for bogey during a round? Never? Maybe once?

With a 10 handicapper, those putts are probably for par, and they make a strong run at the hole b/c they do not want another bogey on their scorecard. Same idea, different #'s.

It's a strange stat, but I can see how it could shake out like it did with a large enough sample size.

I'd be interested to see when those 15-20 footers are missed, what the distance is on the next putt for each level of golfer.
My guess: Scrath golfer, maybe a 6inch - 18inch tap in for par? 10 handicapper maybe 2-3 feet on average. High handicapper maybe 5 feet +, and often missing it. That's just my guess. So the 10+ handicapper may make more, but it's probably for a worse score, and they also set themsleves up to have a greater chance at missing the next one

[Thrdroc]

That is a really good article. For everyone thinking that there weren't enough people, 10 in each category would have been enough to show the differences between each group. With 20 people in each group, you can really start to quantify. With the 70 some people in each group (like done in the article), the stats are about what you would expect in general. Even in you could somehow chart every golfer in the World you should be pretty close to what he got from his survey.

[withdrew]

very good article, top to bottom.
i'm really not in a place to question the guy (pelz), not that i believe everything i read, but he's proven and battle-tested.

that article will absolutely help a player like myself.

[greenail]

It would be interesting to see the difference in data if it was people playing on their regular course. I know that I have much more confidence. When I play my home course just knowing what bounce/breaks to expect changes your play and shot selection.