Round Rating vs PDGA

After using the Round Rating feature a few times and reading all of the FAQ, I am warming up to the feature. I think it will quickly become valuable to both new and experienced players. Of course, experienced players would like to be able to do a rough conversion to the PDGA rating system at least for a little while. The attached graph shows what I have concluded is a reasonable conversion for “league-style” rule compliance.

I will explain my methodology. To convert, it is critical to have an accurate SSA for a course. My league plays the same course all the time and I track all the scores. I use the players who have an active PDGA rating with multiple tournaments to calculate the daily SSA as well as a PDGA-style rating for every player. Over many weeks and hundreds of PDGA player rounds with variable conditions, I have a very stable SSA for the course of 42.4 (18 holes). With the SSA, I can compute the PDGA-style rating for any score. The graph shows the comparison of the PDGA-score and the UDisc round rating.

I feel that the calculations match up well with the UDisc descriptions: more experienced players aim for 200 (~900 PDGA); elite performances will trend from 250 (~1000 PDGA) to 300 (~1100 PDGA).

It is important to note that this only applies to players who follow the rules like a league follows the rules (i.e. pretty strictly). If one takes Mulligan’s, ignores OB, and pulls a disc out of a bush instead of climbing into the bush, it’s not going to be the same. And that’s OK for those people. But, for those who are familiar with the PDGA system and are just trying to get familiar with the Round-Rating system, I hope that the conversion can be a helpful tool to get a feel for the Round-Rating scale.

Hopefully, the round-rating system will catch on fast and will start to become a new standard for players who don’t play in many PDGA events. Next feature (hopefully): predicted scores based on average round-rating to allow for competitive player between different skill levels (if you read my posts, this is a common theme).

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I’m not a data geek, but isn’t your conversion graph based on the flawed assumption that the same score will get the same PDGA rating?

Over the years, I have played tournament rounds on my local track that have deviated by 60 rating points for the same score on the same layout. The weather and the propagators attending can really shift ratings.

I really support the idea of UDisc calculating handicaps, but I don’t see the point of comparing the two different rating systems.

Hi Matt,

You are correct. In tournament play, the same score will not produce the same rating all the time. But, I think that the new UDisc round rating is based on averages as well so will produce the same rating for the same score. But, is that always a flaw? Wind and weather are certainly factors. I see the SSA for my league change from week-to-week (and thus the rating for a certain score changes). What I found is that it didn’t change as much as I would’ve expected. We had a windy week and the SSA only went up by 0.9. So, the idea for me is to look at it as an average of how a course will play. I believe that it is the same thing that UDisc is doing. Ideally, a player can play many different courses and still understand their progression and day-to-day performance. And sure, if one day is windy, a player should expect that their round-rating will likely look a little worse and be ok with it.

The point of comparing the systems for me is two-fold. First, most of us are familiar with the PDGA system. By providing a conversion, people can immediately start to understand the UDisc system without waiting to build up a resume of ratings. I hope it leads to faster adoption. Second, I feel that the graph may help others to understand the FAQ that UDisc has shared as quoted in the initial post. It shows the non-linearity and it shows what they mean by “experienced” and “elite.”

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Hi Pat,

You clearly enjoy playing with the data available and more power to you.

When it comes to the adoption of the casual round ratings, my take is that we should be celebrating the differences and strengths of the two rating systems rather than trying to create simple translations. A lot of the confusion and kick back seems to come from people not reading the FAQs and conflating the two approaches too heavily.

Anyway, good luck with your league and hopefully UDisc will start using these round ratings for a noble purpose like calculating handicaps. Otherwise they may potentially become just another number for disc golfers to obsess over.

Hi Matt,

I just want to follow up with one other thing I use the conversion for. I effectively have a handicap generator that allows my daughter and I to play head-to-head (it calculates an expected score on a course for each of us). However, it requires a good SSA value. Unfortunately, the SSA values that are publicly available (dgcoursereview) are really suspect. With a PDGA rating calculated from a UDisc round rating, I can back-calculate an SSA value that so far (3 courses) seems much more accurate than the ones I’ve been using. And they should be, because UDisc has more data than anyone!

Sometimes, I have to remember to get out and play instead of grinding away on my cute little spreadsheets! Maybe that would up my rating (about 830 PDGA/173 UDisc)!

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And I just want to add that I’ve found out that round ratings will adjust over time as more data is collected, which makes sense if a hole suddenly has all of its rough cleared or a key guardian tree falls.

Source: @smerchek in beta test chat

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Willing to share your handicap generator?

All my stuff is in Google Sheets. A basic calculator that does all the conversions would be pretty easy to share. If you want to track a league, there is a bit more work involved as you have to look up the PDGA ratings, download the league results and cut and paste every week. Can I share a Google Sheet Link here? Let me know what you are interested in and I can think about how to share a sheet and basic instructions.

Initially was asking about your head to head handicap generator you use with your daughter for my family to use, but if you’re are willing to share a league handicap system I would love to see that. We run 2 leagues and have tried various formats and are considering trying a handicapped league for winter as turnout is too low in most divisions.

Hi Jeremy,

The one my daughter and I use tracks all our scores, has course inputs, graphs, and all sorts of stuff. With your interest, I put together a sheet that does the basics of the handicapping. There is no weighting to the handicapping; it is just a pure predicted score based on the player’s average UDisc/PDGA rating. Try it and see if it works with the link and let me know.

If this works, we could think about a league one. My league one doesn’t handicap anything because we have different classes. It’s main function is to help us get players into the correct class.

DG Handicap 1.0

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I think the curve is more exponential. I think 300/1000 should intersect.

Looks like 300 is too powerful… -22 and 1098 rating?

The UDisc FAQ says “Yes, a round can be rated higher than 300, but it will be exceedingly rare. We anticipate that fewer than 1% of all performances will reach that upper echelon.”

In my league data, we often see scores around 1000-1020 and we’ve seen a 1050, but we’ve never seen a 1100. Based on the quote and the data, it seems that 300 lines up with 1100.

How often are 1000 rated rounds? Overall probably less than 1%.

Brodie posted he got 312 on a round.

Your league is not normal if those numbers are accurate.

Hi Jesse,

The top four players in my league have official PDGA ratings of 1000, 999, 989, and 979. So, they average close to 1000 every week. There are 54 PDGA rated players in my league with the lowest at 808. Thus, we have a good range and all of their rounds go to establish the SSA each week.

Additionally, Kuba’s data mentioned earlier in the thread matches my data almost spot-on (with 500 data points).

Lastly, even the rule-of-thumb of PDGA = UDisc x 2 + 500 method that is mentioned above matches well in the 900-1100 range.

The fact that Brodie got a 312 (PDGA 1120 by my equation) shows that an 1100 round is incredible. I think that’s the less than 1%. The difference between UDisc 250 (PDGA 1000) and a UDisc 300 (PDGA 1100) is really quite large because there just aren’t strokes available to improve at that level.

I hope this helps settle things in your mind.