Hey Guys,

Where I play we primarily play 2 shot 8-ball, but I think the question extends to all cue sports.

We currently use a 'custom' system for player ratings that is uses
- results from a couple of round robin tourneys (ranking events)
- Results (games won %) from the two top leagues.
- Numbers from 40-125, where > 100 is usually top 16 in the state.

I think an ELO type system could be applied with a bit of thought to allow knockout tourney results and other additional stat (master breaks etc) to be included.

Questions:
- What ranking systems have you seen for cue sports?
- Where would you start if putting an ELO type system together?

Sorrow

The best ranking system is who wins the most money.

I always suspected that Jamie Gold was better than Barry Greenstein

Barry greenstein has probably had years larger than Jamie gold's life earn.

Thats a bad analogy. The games cant be compared together.

I didnt think poker and billiards went hand and hand. Considering billiard tourneys usually have a set amount of players to enter and there is a minimal luck factor in the game.

Sure the analogy was flawed, but cash is a terrible way to rank people.

There is plenty of variance in cue sports at the top level, especially in 8 and 9 ball where the break is so important. Even more so when you are in a winner breaks format.

I'm looking at how to objectively compare player performance across multiple events with different structures.

All ranking systems have flaws, but something like the ELO system as applied to chess could be applied to pool with some thought.

Time to resuscitate this.

I've been working on this on and off since my original post.

I tried an ELO calculation using the same numbers as chess, based on individual frames but found that player ratings were far too volatile, with ordering affecting results.
eg. PlayerA v PlayerB: 2-1 WWWLLLW gave (sometimes significantly) different points change than LLLWWWW.

I've now switched to a lookup table after someone suggested the Australian squash ranking system worked quite well - http://www.squashmatrix.com/MatrixTable.asp

What interested me was the discussion that players from two different states with similar ratings would actually be evenly matched (ie. The ratings system was close to accurate) even if they'd never shared an opponent.

I've significantly changed the numbers used by the squash guys, and experimented with a real set of matches with players that I know... and it seems to work! New players generally find their rating within 40 matches against an established pool, and the system is sensitive enough to clearly show ebbs and flows of form over time.

I've also started building a web application for managing leagues and entering results, so that at least my leagues may be able to use the system in future.