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Snooker Rating System

Postby SnookerAnalyst

I've created a rating system for professional snooker players, similar to the Elo system devised for Chess. I've seen earlier versions applied to snooker but I don't think that there is another active version at the moment. See http://www.snookeranalyst.com/ratings-post1/ for more details.

The ratings will be updated after every tournament, with the change to each player's rating based on the score in every match they played as well as the strength of the opposition faced. For the lower-ranked players in particular I would suggest that it is a far better guide to their ability than the world rankings.

No real surprises at the top of the ratings - Selby, O'Sullivan, Higgins & Robertson are the Top 4. Quite a lot of variation further down though with Xiao Guodong rated 23th, Jack Lisowski 25th and Michael White 30th. Stephen Hendry is down in 46th alongside the likes of Steve Davis, Ken Doherty & Jimmy White. Jamie Cope was the biggest surprise for me - down in 60th place after a poor run over the last year.

I'm hoping to be able to include charts to show how the ratings of different players have changed over the last few years - might take me a bit of time to set up though. With the ratings changing after every tournament it should provide a more informative picture than the world rankings.

There's further information on my website. Please let me know if my explanation of the system isn't clear enough or if you'd like more details.

Re: Snooker Rating System

Postby Bourne

Ronnie in 2nd :chin: Does this system weight the PL as the most important tournament in the calendar :irk:

Re: Snooker Rating System

Postby SnookerAnalyst

I haven't taken into account the PL - just ranking events & the Masters. This system doesn't penalise players for missing tournaments, which is the main reason why Ronnie has dropped down the rankings but is still doing well here. When he has played then he's generally done well - he's still among the favourites for every event he turns up for.

Re: Snooker Rating System

Postby Roland

People should read how the system works before trying to find anomalies. There's a great deal of thought and mathematics that's gone into it and it's pretty good I'd say and a lot fairer on the newcomers to the tour than the starter points this season.

I know a lot of members here have strong opinions on the ranking system so I guess it's feedback time for SnookerAnalyst.

Keep it on topic please :santa:

Re: Snooker Rating System

Postby Wildey

Ronnie lost in 3 1st round of ranking events last season and only one final in 2 years where as Mark Williams made 4 ranking finals and World semi in the last year.

Re: Snooker Rating System

Postby Bourne

Wild wrote:Ronnie lost in 3 1st round of ranking events last season and only one final in 2 years where as Mark Williams made 4 ranking finals and World semi in the last year.

<ok>

This system is bonkers :gag:

Re: Snooker Rating System

Postby Tubberlad

Pretty interesting stuff, I have wondered how the snooker rankings would work if you used a similar system to what's used in football.

It's interesting to see the top four are highly established players, even though I'm a little surprised O'Sullivan is up there. Still though, nice work and it will be interesting to compare both lists over the rest of the season...

Re: Snooker Rating System

Postby Wildey

Bourne wrote:
Wild wrote:Ronnie lost in 3 1st round of ranking events last season and only one final in 2 years where as Mark Williams made 4 ranking finals and World semi in the last year.

<ok>

This system is bonkers :gag:


its not bonkers its different way to look at it and im going to take a closer look at it but on first impression that what i highlighted stood out like a sore thumb.

Re: Snooker Rating System

Postby Tubberlad

I would praise the effort put in, but I would also encourage to weight matches based on the tournament involved: should the Masters, UK & World Championship carry a different weighting? As far as I can see this is not the case.

The effort is something else though, fair play.

Re: Snooker Rating System

Postby Monique

There is no need to weight tournaments differently because, as it is, the longer the format the likelier it is that the ranking of a player will be influenced by a exceptionally good or bad result. This system is probably the best reflection of the players current (known) ability but does not give any indication on their dedication (*)
Contrary to other systems it does make it quite obvious which players are on the up - especially interesting for the younger ones who are less well known - and which of them are clearly in free fall.

(*) this is not totally true as I suspect that Williams relatively lower rating than expected is related to his absolutely woeful performances in the PTCs this season but then the simple truth is that he's not trying at all there.

Going by this I'd say that there is more chances for Hendry to be out of the top 32 by the end of the season than for him to be back in top 16, which, sadly enough, is exactly what my guts feelings are telling me for a while. But this is another debate.

Re: Snooker Rating System

Postby SnookerAnalyst

Thanks for the comments - there is a good balance here. I'll respond to more of them in the next couple of days.

One of the big questions for me was whether or not to apply a smaller weight for the PTC events. I chose not to because these events are important for lower ranked players - and they are the players I'm most interested in because of the bias in the official system. The way that PTC events are bunched up in the calendar means that they arguably have an undue influence over the ratings at this time of the year - on the other hand they are the best guide to a player's current form.

It is possible to assign a different weight for the PTC events depending on the ranking of the player - but I didn't want to over-complicate the system at this stage. I'll review some of these issues at the end of the season.

Re: Snooker Rating System

Postby Wildey

Monique wrote:There is no need to weight tournaments differently because, as it is, the longer the format the likelier it is that the ranking of a player will be influenced by a exceptionally good or bad result. This system is probably the best reflection of the players current (known) ability but does not give any indication on their dedication (*)
Contrary to other systems it does make it quite obvious which players are on the up - especially interesting for the younger ones who are less well known - and which of them are clearly in free fall.

(*) this is not totally true as I suspect that Williams relatively lower rating than expected is related to his absolutely woeful performances in the PTCs this season but then the simple truth is that he's not trying at all there.

Going by this I'd say that there is more chances for Hendry to be out of the top 32 by the end of the season than for him to be back in top 16, which, sadly enough, is exactly what my guts feelings are telling me for a while. But this is another debate.

you cant weight PTC on a par with the World Championship thats just redicioulas and players like Xiao Guodong at top 25 based on excelent PTC without even qualifying ever for the World Championship or lets face it many main venues.

i do think however the system overall is better BUT it needs to be refined.to difirentialice beteeen PTC and Main Rankers.

sorry but Ronnie is no way no 2 best player over the last 2 years in a million years.

winner=0
Runner up=1
Semi finals=2
Quarter finals=2
Last 16=1
Last 32=4
Did not enter=3

Re: Snooker Rating System

Postby Roland

PTC and main rankers - one frame difference in some of them. I'm in favour of keeping strong weighting in PTCs as there's nothing else around at the moment and building them up into individual little rankers as they become more established. I don't see how you can argue that Xiao Goudong and Li Yan don't deserve to be top 32 in the world at the moment because they clearly are top 32 players right now.

Re: Snooker Rating System

Postby Wildey

Sonny wrote:PTC and main rankers - one frame difference in some of them. I'm in favour of keeping strong weighting in PTCs as there's nothing else around at the moment and building them up into individual little rankers as they become more established. I don't see how you can argue that Xiao Goudong and Li Yan don't deserve to be top 32 in the world at the moment because they clearly are top 32 players right now.

their are totally different events ffs you cant Rank players Based on PTC = to UK or we might aswell just say buck it lets play everything over a weekend and Rank players Acordingly.

Guodong hardly featured in Aussie or Shanghai.

Re: Snooker Rating System

Postby Monique

If anything Wild they are harder to win than a tournament like the Welsh. They have to play more matches, without any seeding protection, within a very punishing schedule. On the final day they possibly play as much as 28 frames while in any major it's never more than 19, even in the WC. The fact that it is squeezed over 3 days doesn't make it easier, quite the opposite.

Re: Snooker Rating System

Postby Wildey

Monique wrote:If anything Wild they are harder to win than a tournament like the Welsh. They have to play more matches, without any seeding protection, within a very punishing schedule. On the final day they possibly play as much as 28 frames while in any major it's never more than 19, even in the WC. The fact that it is squeezed over 3 days doesn't make it easier, quite the opposite.

dont give a toss how hard they are to win thats neither here or there you rank events based on prestiege.

im sorry SnookerAnalyst thats not a criticism of the system its far better potentially than we got currently but it needs refining or we will end up with a World no 1 that spends more time in IBIZA than playing snooker.

Re: Snooker Rating System

Postby Roland

Weight the PTCs accordingly (i.e. 75% of "full" standard ranking events) and allow players to miss a certain number of events per year which won't affect their ranking then you're some way to being where we need to be.

Of course as if people don't need reminding, there is the hideous concept of a money list based ranking system being considered. You think this alternative suggestion throws up anomalies, just wait to see how bad it'd be with a money list!

Re: Snooker Rating System

Postby Wildey

ive now read through the whole post http://www.snookeranalyst.com/rating-summary/ and i have to say i like it but it will have to be used in a flat system 128 because with a tier system you got players down the order beating easier players thats higher up the scale than them where as players inside the top 32 has to beat Top 16 players and if they dont they slip back being replaced by players who only beat top 48 players.

if thats clear lol

Re: Snooker Rating System

Postby Monique

Wild wrote:
Monique wrote:If anything Wild they are harder to win than a tournament like the Welsh. They have to play more matches, without any seeding protection, within a very punishing schedule. On the final day they possibly play as much as 28 frames while in any major it's never more than 19, even in the WC. The fact that it is squeezed over 3 days doesn't make it easier, quite the opposite.

dont give a toss how hard they are to win thats neither here or there you rank events based on prestiege.

im sorry SnookerAnalyst thats not a criticism of the system its far better potentially than we got currently but it needs refining or we will end up with a World no 1 that spends more time in IBIZA than playing snooker.


Well basing the ranking on prestige is pretty unfair in my book. Hearn said he did not want to reward mediocrity, I reckon then that the goal then is to reward excellence. Well excellence expresses itself in minor events as well as in majors. ROS 147 in Fürth was not easier or less remarkable than the ones he made in the WC and may prove more important for the development of the game in new markets.

Re: Snooker Rating System

Postby Wildey

147s mean rubbish in whatever event its done in

and monique dont talk utter garbadge prestiege happens in all sport regarding Rankings why should snooker have to rely on having rankings based on success in minor events.

Re: Snooker Rating System

Postby Monique

Prestige happens but that does not mean it should be the main criteria for ranking. Ranking should be based on success and excellence, full stop. There is no reason that a best of 5 based event is rewarded with nearly 4 times the ranking points earned for a PTC only because it has inherited the "prestige" of a former tournament that had an entirely different format. And there is no reason that a tournament like the Welsh, that for all its history is played in a rather shabby place with poor audience and isn't exactly a long format event gets more ranking points than the Paul Hunter Classic that attracted a massive crowd.
As for 147 it may "mean nothing" but it does create a lot of buzz and God knows the sport needs it. No sport can survive without an audience, never forget that.

Re: Snooker Rating System

Postby mediter

Yeah, 147 always creates a great buzz !

And you can say that wild is the 147-machine of snooker messageboards :-) I remember a few years ago someone wrote here that snooker island = wild <laugh> <laugh> Who could ever forger his brilliant and extremely heated Goat; Hendry or O`Sullivan arguments against Seifer island hatah... I remember both were banned numerous times atthe BBC messageboard because of their language, insults and abuse :-)

But what I am saying, is that those arguments are just great. In the country where I live, there has been messageboard culture where they are just saying "Heil Hitler" in a different ways. And the worse part was that in every other aspects of life too. So there were no real arguments, just saying Heil Hitler in a different ways. Luckily, that has pretty much come to an end, and the kind of freedom people have in UK have come to replace.

Re: Snooker Rating System

Postby Roland

Pleased to hear it mate, except this topic is about rankings and not culture.

Re: Snooker Rating System

Postby SnookerAnalyst

Some thoughts on the responses so far:

Note that I'm not actually recommending that this replaces the current system. I'd quickly change my mind if the players themselves expressed an interest - but I don't think it is a transparent enough system as players wouldn't automatically know what they had to do to (e.g.) break into the Top 16. I think players would also expect guaranteed rewards for reaching the latter stages of events.
I do hope that it helps to highlight some of the biases in the current system though and is used to try and identify a fairer system for ranking players. I do think that there is a potential use for the system in the amateur game - although I have to admit I'm not very knowledgeable about this. There may also be a justification for using it to complement the ranking system (e.g. Top 64 from rankings qualify for next season + 8 highest players on the rating system who haven't automatically qualified).

Wild - I partly disagree with you comments - I think that this system works well regardless of the way that tournaments are structured (and is much better than the current ranking system in this sense). However, I think it is true that the introduction of the flatter PTC events will have helped to strengthen the system due to different players being drawn against each other.

There have been a few comments about whether Mark Williams is under-rated by this system given that he's reached 4 major ranking finals in the last year. I'll carry out some more analysis of his rating but some quick comments for now:
1. His ranking was higher (1,004) after the Shanghai Masters. It has fallen since then because he's only won 5 frames in his last 3 PTC matches.
2. During the Australian & Shanghai events he actually only beat 2 Top 16 seeds. Indeed, he didn't play anyone from the Top 16 in Australia. Contrast this with Stuart Bingham who beat 5 Top 16 players during the same tournaments. Without wishing to play down Williams's achievement, I think that the rating system does offer a valuable alternative perspective on how players have performed.

I've had a go at at 'predicting' the results of the UK qualifiers using the ratings (see the discussion topic on this subject). It's not what I designed the system for but in theory it should work reasonably well. If nothing else then I'm sure that some of you will take satisfaction from beating me!

Re: Snooker Rating System

Postby Wildey

the pressure of playing for A Established event with history and prestiege is greater than in PTC where players can relax more therefore having rankings based so heavy on PTC being equal Cant be right and it has to be separated from main rankers.

the fact they tough to win over a weekend is neither here nor there and doesent matter at all.

Ronnie's form is not top 8 and its not strugling for top 16 status its about 10th or 11th thats his correct possition regarding current form.

so really you need a system somewhere in between your system is top heavy towards the PTC and players form in that.

Re: Snooker Rating System

Postby SnookerAnalyst

I've just had a quick look at halving the weight given to the PTC events this season. Selby & Ronnie stay 1st and 2nd but Williams moves back into 3rd. I'll review the weights properly at the end of the season but I'm not sure it will make a significant difference to the ratings.

If the PTC events were spread out more evenly across the season then I don't think it would be an issue at all. They probably influence the ratings a bit too much at this time of the year, but once more of the full ranking events are played then I'm sure that everything will re-adjust.

Re: Snooker Rating System

Postby Roland

I think the PTCs need to be weighted to some degree, classing them as half an full ranking event for example is way off. They should be at least 75% and there's no other form guide at the moment because there are no other tournaments. I was saying to Wild and others that Xiao Goudong and Li Yan have already proved themselves bona fide top 32 players through the PTCs and whichever ranking system used should reflect this.

Re: Snooker Rating System

Postby Wildey

Sonny wrote:I think the PTCs need to be weighted to some degree, classing them as half an full ranking event for example is way off. They should be at least 75% and there's no other form guide at the moment because there are no other tournaments. I was saying to Wild and others that Xiao Goudong and Li Yan have already proved themselves bona fide top 32 players through the PTCs and whichever ranking system used should reflect this.

no they have not proved themselves as top 32 players they have prooved themselves playing second tour ie PTC.

this is Xiao Record

2 last 32 and 1 last 16 in 6 years and 1 last 32 and the last 16 was as a wild card so only once has he made a venue. so no he is nowhere near a top 32 player

Re: Snooker Rating System

Postby Roland

At this moment in time he is a top 32 player, not 6 years ago!

<doh>

UK and Worlds should have higher points tariff than the rest and PTCs less but weighted so they are 70-80% of standard ranking. That's my judgement going on feel.

Re: Snooker Rating System

Postby Wildey

Sonny wrote:At this moment in time he is a top 32 player, not 6 years ago!

<doh>

UK and Worlds should have higher points tariff than the rest and PTCs less but weighted so they are 70-80% of standard ranking. That's my judgement going on feel.

at the mome he hasent qualified for a main venue since 2007 buck the PTC thats second tier events and until they get higher points tariff thats where they stay so hes not a top 32 players end bucking of <doh>

what part of that bucking line cant you get.