Share your New Strokes Gained Data from GAME Golf!

[iacas]

8 hours ago, BenBilly said:

"my research" meaning in this context comparing my calculation on my shots with GG calculation. I did not see anywhere that kind of comparison yet and I am just asking not to use "my research" or "my conclusion" if your prefer. Using one of the user conclusion and talk to GG is not very fair even if your are "partners"... 

Please delete my post and my user.

Thank you,

You haven't produced anything new, nothing we didn't already know. We've done those same exact calculations for entire rounds on other users. This is simply more data that backs the same conclusion at which we'd arrived.

We do not delete accounts or posts. I encourage you to look around. I think you'll discover that you've stumbled onto a great site with lots of great people.

[RandallT]

19 hours ago, BenBilly said:

I have been calculating strokes gained just after the publication of Mark Broadie's book round after round on a spreadsheet noting every distance and lie (fairway, rough, sand, recovery, penalty or green) of the ball. 

On my last round of Game Golf, I was very surpised to see that I lost 4,91 strokes compared to a scratch player as I had 32 putts on that day...

I decided to check the calculation myself and discovered that the number of strokes lost on putting provided by Game Golf is not accurate and strongly off : 

Putting stroke calculated with the Mark Broadie's method: 2.67

Putting stroke calculated provided by Game Golf : 4.91

The concerning part is that the difference between the two calculations is 2.24 strokes !

A difference of 2.24 strokes on putting means that the complete calculation of strokes gained is off. The impact of 2.24 shots difference means that the calculation for the 4 parts (off the tee, approach, short approach and putting) would completely changed as all parts are related together..

Strokes gained putting Game Golf_inquiry BenBilly Willocq.pdf

I took a look at your actual round, and I've got a few comments that may be relevant. @iacas comments above are also good.

1. I ran your chart above in blue against my own strokes gained tool, and I came up with a similar number for strokes lost. So congrats to us both- we've both applied Broadie's numbers correctly (let's hope!).

2. I looked at your round and I think I spot a flaw in the methodology of converting their interface to our Broadie analysis. It would also make the putting numbers worse, which is what happened. Take your 4th hole, for example. Here's a screenshot.

As you can see, your first putt (Shot 3) is NOT a 15-footer. The first putt is shown in white, and the second putt is shown in yellow.  The first putt rolled 15ft, and left you 9 ft past the hole, which you sank.  Eyeballing that, I would say GG thinks your first putt was 6 or 7 feet.  So GG thinks you 2-putted from 6/7ft. But we plugged in a first putt of 15feet, because the interface says Shot 3 was 15 feet. Confusing.

So our calculations of a two-putt from 15-feet might lose 0.2 strokes.  A two-putt from 6-feet would be a loss of .6 or .7 strokes.  So that one hole could account for a half stroke difference right there.

Similarly on the 12th hole, your chart shows a 30ft putt and a 10ft comebacker. Visually, it appears that you were 20ft away for the first putt, but you putt the ball 10ft past the hole. Then you hit that. So in reality, you should use 20ft for the first putt.

3. Lastly, there is lots of room for the numbers to be off, particularly when you compare pga vs scratch (different baselines). I once ran Broadie's exact numbers for a round where Rickie Fowler won a tournament. The PGA shotlink system gave the exact distance to the hole on every shot/putt. Here's the chart:

http://www.pgatour.com/statsreport/2015/09/07/strokes-gained-at-deutsche-bank.html

	Strokes gained per round (ranks in parentheses)					Rank
Rickie Fowler	Total	Drive	Appr	Short	Putt	out of
2015 Season	1.4 (15)	0.2 (76)	0.5 (28)	0.3 (31)	0.4 (28)	205
Deutsche Bank Championship	3.7 (1)	0.4 (21)	1.6 (5)	0.0 (44)	1.8 (2)	74
Round 1	4.7 (9)	0.9 (10)	1.2 (27)	-0.4 (62)	2.9 (6)	98
Round 2	3.5 (17)	0.5 (33)	2.9 (5)	-0.1 (59)	0.2 (43)	98
Round 3	2.9 (11)	-1.0 (68)	0.7 (26)	0.2 (36)	3.0 (3)	74
Round 4	3.7 (10) 3.7 (matches)	1.0 (10)2.0	1.4 (14)1.1	0.3 (32)-0.8	1.0 (17)1.4	74

 

(my results for strokes gained shown in RED) So comparing a pro with exact numbers against Broadie's published charts, the numbers evened out, but for putting it was off by 0.4. For driving, it was off by 1.0.  So if a pro on a pro course with exact numbers has this kind of variability when comparing against Broadie data, I imagine we shouldn't be too surprised when coming up with numbers that are off as well. It is useful for a general feel, but I don't get too hung up with differences of 1 or 2 strokes in any category.

 

 

 

[RandallT]

FWIW- I re-ran the numbers against Broadie, based on the visual look of every putt on your round GG. Here's an example:

For the 12th hole, I used an initial putt of 20ft (not the 30ft shown) since the second putt (shot 6) appears to be  a 10-ft comeback putt.

I see you losing closer to 4 putts to pros (3.7ish, but the tenths digit is likely not too accurate). But that still is different than GG saying you lost 4.91 to scratch players. Not sure what might account for why you'd lose one more stroke to scratch players than we are calculating you'd lose to pros.  I think the GG team is pretty good, and they might shed some light on this. 

[BenBilly]

11 hours ago, iacas said:

Your third hole you were 27 feet away. Expected strokes: 1.95. If you two-putt, you lose 0.05 strokes.

Lo and behold, you two-putted, and lost… 0.05 strokes. Same as if you hit it to two inches, or 33', and made the second putt.

You are short cutting the calculations for putting and you miss a lot of information if you don't take the second/third putts into consideration: 

From my example:

H3: first putt from 27 feet gives -0.28 stroke (lost)

H3: second putt from 5 feet gives +0.23 stroke (gain)

The total from 27 feet for 2 putts is indeed -0.05, that's fine. But it's also the result of -0.28 + 0.23 = -0.05 

Saying that the second/third putts are irrelevant is not right as you don't know how your are then putting after this putt of 27 feet.

To work on weaknesses, it is important to know that the 27 feet was a bad shot as it finished 5 feet from the hole. However, holing the 5 feet was a good shot. Two different quality of shots, then. If you don't pay attention to the precise breakdown, you have no clue on where to work on...

This is why GG needs to provide the SG, the lowest granularity possible. 

 

 

[Club Rat]

9 minutes ago, RandallT said:

based on the visual look of every putt on your round GG

Question? Do putts for "bird or par" have any relevance to strokes gain over putts for bogey or dbl bogey? 

[saevel25]

5 minutes ago, BenBilly said:

You are short cutting the calculations for putting and you miss a lot of information if you don't take the second/third putts into consideration: 

From you first post on comparing to Game Golf you were comparing straight up strokes gained putting as a total, not breaking it up into parts to see which part of your putting is a weakness. 

If you break it up then you have to look at each putt. That still doesn't change the total of your strokes gained putting if you just take the short handed method on it. 

1 minute ago, Club Rat said:

Question? Do putts for "bird or par" have any relevance to strokes gain over putts for bogey or dbl bogey? 

Pars, you probably are looking at around average strokes gained putting. Lots of two putts, incremental increase and loss of strokes gained. 

Birdies should have a higher strokes gained putting and tee to green. Just basing it on the odds of making 45 ft putts versus hitting a great iron shot to inside 20 ft and draining a medium length putt. 

Bogies or worse just depends on the long game and how the hole plays out. If you chip it close and tap in bogey your strokes gained putting should be similar to a par putt, but your tee to green should be crappy. Something like that. 

[BenBilly]

9 minutes ago, RandallT said:

FWIW- I re-ran the numbers against Broadie, based on the visual look of every putt on your round GG. Here's an example:

For the 12th hole, I used an initial putt of 20ft (not the 30ft shown) since the second putt (shot 6) appears to be  a 10-ft comeback putt.

I see you losing closer to 4 putts to pros (3.7ish, but the tenths digit is likely not too accurate). But that still is different than GG saying you lost 4.91 to scratch players. Not sure what might account for why you'd lose one more stroke to scratch players than we are calculating you'd lose to pros.  I think the GG team is pretty good, and they might shed some light on this. 

I suspect that the all issue with GG is to determine the exact location of any shot compared to the pin. They measure the distance of the shot, not the distance to the pin...

This explains why they are off I believe.

 

 

[saevel25]

9 minutes ago, BenBilly said:

I suspect that the all issue with GG is to determine the exact location of any shot compared to the pin. They measure the distance of the shot, not the distance to the pin...

This explains why they are off I believe.

They still can get distance to the pin. It's all GPS points. They pin is also a GPS point. So it's not too hard to just reference the pin instead of the next shot. 

[iacas]

1 hour ago, BenBilly said:

You are short cutting the calculations for putting and you miss a lot of information if you don't take the second/third putts into consideration: 

I'm not. Not when you consider just "strokes gained - putting."

The only area ignoring the distances of second and third putts hurts you is in analyzing whether you're a good or poor putter from various ranges. For example, if you have a 33' putt (expected: 2.0) and you hit it to 8 feet (expected 1.5), you've lost half a stroke putting with the first putt. You should have hit it to a place where your expected total is 1.0.

If you subsequently make the second putt, you gain that 0.5 right back, so your total for the hole is 0.0. If you miss, you lose the half stroke on the second putt as well, which means you lost 1.0 strokes.

But none of those totals are at all affected by the length of the second putt. If your first putt is expected to take 2.0 strokes, and you take 1, 2, or 3 strokes, you gain 1, break even, or lose 1 stroke putting regardless of how long any second or third putts are.

1 hour ago, BenBilly said:

From my example:

H3: first putt from 27 feet gives -0.28 stroke (lost)

H3: second putt from 5 feet gives +0.23 stroke (gain)

The total from 27 feet for 2 putts is indeed -0.05, that's fine. But it's also the result of -0.28 + 0.23 = -0.05

Right - you didn't need to do the math on the second putt. It's a waste of time and tracking. It needlessly clutters the chart.

Plus, as @RandallT pointed out, you're doing it wrong. You're using the distance you hit the putts, not the distance to the hole as you should be.

1 hour ago, BenBilly said:

To work on weaknesses, it is important to know that the 27 feet was a bad shot as it finished 5 feet from the hole. However, holing the 5 feet was a good shot. Two different quality of shots, then. If you don't pay attention to the precise breakdown, you have no clue on where to work on...

This is why GG needs to provide the SG, the lowest granularity possible. 

As I said above, that's the only thing that you're gaining. And you're not even gaining that well, because you're doing that wrong.

For example, for your seventh hole, you put down 12 feet and 5 feet. The shots look like this:

Since those are almost linear (we don't have to do any trigonometry, just addition and subtraction), your first putt was actually about 7 feet (you hit the first putt 12 feet, 5 feet past the hole).

So you aren't even doing that right, because here's what you said:

From 12 feet pros take about 1.68 putts. You took two, and correctly got the math right there: (0.55-0.23 = 0.32 strokes lost, 2 - 1.68 = 0.32 strokes lost).

By your math, you lost 0.32 strokes in two-putting from 12 feet.

In reality, you lost 0.58 strokes on that hole. Why? PGA Tour pros average 1.42 putts from 7 feet. If you wanted to break it down like that, you should have written:

H7     7     -0.81
H7     5     +0.23

You should not write down the distance you hit the shot. That's not how Strokes Gained works. You need to write down the distance remaining to the hole. In this case, 7 feet, and then 5 feet.

So you would look at this one hole, for example, and say "I need to do better on my 12 foot putts. I lost over half a stroke with that." You'd think your five-foot putts are good since you gained nearly a quarter of a stroke.

When in reality your 5-7 foot putting cost you 0.58 strokes: you lost 0.81 with your 7-footer and gained the same 0.23 back with the five-footer.

And that's beside the main point I was making about why you don't need to care about the second or third putts: because GG currently gives you "strokes gained - putting" as a whole, the distance of second and third putts is not relevant in disputing the entire number. You simply need to know the expected putts and the number of putts taken from the original distance to the hole.

1 hour ago, saevel25 said:

From you first post on comparing to Game Golf you were comparing straight up strokes gained putting as a total, not breaking it up into parts to see which part of your putting is a weakness.

If you break it up then you have to look at each putt. That still doesn't change the total of your strokes gained putting if you just take the short handed method on it. 

Bingo.

BTW, @BenBilly, if you're interested in stats, and working on your game, and all of that… you should check out one of our other partners in 2016: http://lowestscorewins.com/. Their work is going to be integrated throughout the year into GAME Golf, too.

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2 hours ago, BenBilly said:

I suspect that the all issue with GG is to determine the exact location of any shot compared to the pin. They measure the distance of the shot, not the distance to the pin...

This explains why they are off I believe.

I missed this one before.

It doesn't explain why GG is off. As @saevel25 said the distance between two GPS points is easily calculated.

Two things are still likely "off" a little bit.

1. Your data. You need to stop writing down the distance your putts travel and start writing down the distance you have left to the hole. This is a big boo-boo.
2. The GG strokes gained stats don't seem to be perfect yet. That said, the math is pretty simple, so the error may just be in their data? Maybe too many GGers aren't editing their rounds, or something like that?

I feel bad about your two years of data. I don't think I'd trust any of the putting data if you've been entering the wrong distances for each.

[BenBilly]

Dear Admin, 

Please note that the calculation is correct as from 12 ft (I measure the distance to the hole with my own feet, yes...) it takes 1.68 strokes for a pro. 

I therefore lost -0.32 stroke in total not -0.58 as you indicated ? How can that be ?

From 5 ft a pro takes 1.23, I holed it gaining 0.23 stroke.

The breakdown of the two putts is then: 

-0.55 from 12 feet 

+0.23 from 5 feet

Total equals -0.32 and tallies with the quick calculation above.

I have developed a spreadsheet template which works perfectly and really know what I am talking about (see the explanation on my blog below on SG and how to compare with all handicaps) !

http://golf-made-in-us.blogspot.com/  

I came here to share something and instead got misinterpretation from the very beginning calling my calculation "wrong" in all posts. 

All the best, 

 

[iacas]

3 hours ago, BenBilly said:

Please note that the calculation is correct as from 12 ft (I measure the distance to the hole with my own feet, yes...) it takes 1.68 strokes for a pro. 

I therefore lost -0.32 stroke in total not -0.58 as you indicated ? How can that be ?

Because your first putt was from 7 feet, not 12.

3 hours ago, BenBilly said:

I came here to share something and instead got misinterpretation from the very beginning calling my calculation "wrong" in all posts. 

Your calculations are wrong if you're basing them on how far you hit each of your shots. You lost 0.58 strokes to a PGA Tour pro because your first putt - the one you hit 12 feet - was only 7 feet away from the hole.

I feel this has been pretty clearly stated by myself and @RandallT.

[BenBilly]

Did you really read my comment ? 

Is all you can say "you're wrong" or do you actually try to create a discussion? 

I am NOT "wrong" as I hit the putt from 12 FT and then from 5 FT, not from 7 FT !!!

This is the reality of my putts that were measured by my own feet !!!

GG might reflect 7 FT (?) and it would need to be corrected if it's the case but my calculation in the blue table indicated in my first post on the subject is 100% correct as I tried to tell you but it seems impossible for you to get it. I am surprised you are the owner of the website with such a disrespectful attitude and stubbornness. 

 

[iacas]

1 hour ago, BenBilly said:

I am NOT "wrong" as I hit the putt from 12 FT and then from 5 FT, not from 7 FT !!!

This is the reality of my putts that were measured by my own feet !!!

GG might reflect 7 FT (?) and it would need to be corrected if it's the case but my calculation in the blue table indicated in my first post on the subject is 100% correct as I tried to tell you but it seems impossible for you to get it. I am surprised you are the owner of the website with such a disrespectful attitude and stubbornness. 

GG doesn't "reflect" 7 feet because ultimately you're responsible for this display.

It's awfully coincidental that on the 12-footer you had a 12-footer and a five-footer and that's exactly what GG shows (i.e. originally a 7-footer), and on the fourth hole, you had a 15-footer followed by a 9 footer… which is what you have in your chart AND what GG shows.

GG is doing the calculations as if you had a 7-footer and a 6-footer. You control the GG locations of shots and the hole. So, if you actually had 12 feet to the hole, and 15 feet to the hole, you're wrong in where you placed the shots in GG, because it is (probably properly and correctly) calculating them as 7- and 6-foot initial distances.

[RandallT]

9 hours ago, Club Rat said:

Question? Do putts for "bird or par" have any relevance to strokes gain over putts for bogey or dbl bogey? 

Hi John!

If I understand your question right, no relevance. I, for one, would have an exploding brain if "strokes gained" calculations were also dependent upon their score on the hole 

@BenBilly- quick question about how you remember this hole below. (kinda amplifies what @iacas is getting at above and he just posted as i was about to hit submit).

I'm curious if this was a 30-footer (initial distance to hole) that went 10-feet past the hole?

Or was it a 20-footer that went 10-feet past the hole?

Or something else not depicted at all?

By your original blue chart in your first post, I read that it was a 30-foot initial putt length.  But Game Golf visually to me shows a 20-footer (you can see that by hovering over the first putt's line segment, and eyeballing that it travelled 30-feet, but 10-feet past the hole).

If Game Golf's picture were to match your blue chart, it would have to show the first putt as travelling 40-feet (the original 30-foot putt length plus 10-feet past). But by GG, the putt only went 30-feet. 

It's a bit confusing I know, as I went through hole after hole after hole of this for some analysis with Erik a month or two ago, and it scrambled my brain a bit 

So what actually happened on this hole? That might get us on the same page. 

[Club Rat]

20 minutes ago, RandallT said:

I, for one, would have an exploding brain if "strokes gained" calculations were also dependent upon their score on the hole 

Haha, guess those two putts for a quad really matter for player improvement.

They give a false sense of a players game analysis in a certain areas.

[iacas]

Just now, Club Rat said:

Haha, guess those two putts for a quad really matter for player improvement.

They give a false sense of a players game analysis in a certain areas.

What does that mean?

If you two-putt for a quad from 40 feet, you've gained strokes with your putting. If you two-putt for a quad from six feet, you've lost strokes with your putting.

Same as ever. For any score.

[saevel25]

Here is my strokes gained data from the previous round. When I am playing I try to guess where parts of my game are at in the strokes gained area. Going into the ninth hole I thought I was broke even on strokes gained putting. I didn't make much, but I had a lot of GIR's and some longer putts. I really didn't have any issue lag putting. I made a 15-17 ft putt for birdie. I was thinking, "Eh, that's probably breaking even then on putting"

The driving is a tad off because they don't count other fairways as a fairway hit though the lie isn't penalizing as the rough. Off the Tee should be a bit better and the approach should be a  bit worse. Maybe closer to 6.00 and -4.20. That is kinda something I think needs to be added to the edited feature. Allowing you to change from FIR to non FIR.

Besides that GIR is KING!!! 

 

[the fish]

2 hours ago, saevel25 said:

The driving is a tad off because they don't count other fairways as a fairway hit though the lie isn't penalizing as the rough. Off the Tee should be a bit better and the approach should be a  bit worse. Maybe closer to 6.00 and -4.20. That is kinda something I think needs to be added to the edited feature. Allowing you to change from FIR to non FIR.

I've noticed at my course they consider an adjacent fairway as FIR. I wish they wouldn't, as it certainly isn't an accurate tee shot if I'm that far over.

I agree it would be able to declare FIR vs not, similar to the slider to declare a putt off the green. I think better than that would be the ability to rank a tee shot or approach shot. Many shots that find the rough are no worse off than a fairway lie. Conversely, on a dogleg you might find the fairway but be blocked from having a shot at the green. Ranking these shots would help make better strokes gained data I believe.