Snooker through the Ages – 1984/85

The 1984/85 season had a total of 119 players, up from 102 the previous year.

There were 74 active players, and their final ratings based solely on their performances in this season were as follows:

Steve Davis was once again #1, but the gap between him and the chasing pack closed. Davis started his season with 3 group-format tournaments, and finished as runner up in the 1984 Singapore Masters, before coming third in the 1984 Malaysian Masters and last in the 1984 Thailand Masters. A return to Knockout tournaments found more success, winning the 1984 Hong Kong Masters, the 1984 Scottish Masters and the 1984 International Open in succession. The 1984 Grand Prix saw him lose in the Semi Final to Cliff Thorburn, but he bounced straight back at the 1984 UK Championship, beating Alex Higgins 16-8 in the final. The new year saw Davis lose in the semi final of the 1985 Classic, and the last 16 of the 1985 Masters, before he won the 1985 English Professional Championship in February. The 1985 British Open saw him lose in the Semi Final, as did the 1985 Irish Masters. Entering the World Championship then, Davis was favourite, and reached the final without too much difficulty. However, this wasn’t to be his year.

Dennis Taylor had established himself as the closest rival to Davis. Ranked #2 by me in the previous season, he had built on his success. During the season he had won the 1984 Costa Del Sol Classic, the 1984 Grand Prix and the 1985 Irish Professional Championship. At the World Championships, he beat Silvino Francisco 10-2, Eddie Charlton 13-6, and Cliff Thorburn 13-5, in a tactical battle where only 1 half-century was scored in 18 frames. He beat Tony Knowles 16-5 in the Semi Final, setting up a meeting with Davis in the Final. What followed is probably the most famous match in snooker history, where Taylor was trailing for the entire match before winning a decider on the black ball in the deciding frame. Steve Davis was still the #1 player, but Dennis Taylor was the new world champion.

Snooker through the Ages – 1983/84

The 1983/84 season had a total of 102 players, up from 77 the previous year.

There were 62 active players, and their final ratings based solely on their performances in this season were as follows:

For the 4th consecutive year, Steve Davis tops the pile. He started the season with a 3-0 loss in the 1983 Hong Kong Masters to Doug Mountjoy, which he avenged 2-1 in the 1983 Thailand Masters before losing in the final. He won his first title at the 1983 Scottish Masters, followed by winning the 1983 International Open.

He lost in the last 32 of the 1983 Professional Players Tournament, then had a run to the final of the 1983 UK Championship where he narrowly lost to Alex Higgins 16-15 in the final. At the turn of the year, he lost in the Quarter Final of the 1984 Pot Black but then won the 1984 Classic. Defeat in the quarter final of the 1984 Masters to Kirk Stevens was a setback, but he then won the 1984 Tolly Cobbold Classic in February, beating Stevens en route to the title.

Another victory followed in the 1984 International Masters, followed by another in the 1984 Irish Masters, meaning Davis arrived at the Crucible having won 3 straight tournaments.

The World Championships was a familiar story for Davis. 10-3 over Warren King in the first round, then 13-5 over John Spencer in the second. The Quarter Final against Terry Griffiths was 13-10, then the Semi Final was a 16-9 win over Dennis Taylor. The final was between Davis and Jimmy White, who had reached his first World final. Davis took an early lead, but White fought back and made it a close result in the end. Davis won 18-16 to win his third World Title and cement his place as one of the great players.

Snooker through the Ages – 1982/83

The 1982/83 season had a total of 77 players, up from 73 the previous year.

There were 34 active players, and their final ratings based solely on their performances in this season were as follows:

Steve Davis continued his dominance. He started the season by winning the 1982 Australian Masters in August, followed swiftly in September by winning the 1982 Scottish Masters, beating Alex Higgins 9-4 in the final. He faltered in the 1982 International Open, losing in the Quarter Final to David Taylor, and similarly lost to Terry Griffiths at the same stage in the 1982 UK Championship.

He returned to winning ways at the turn of the year, winning the 1983 Pot Black, and the 1983 Classic in January. He lost in the 1983 Masters Quarter Final, then made up for this by winning the 1983 Tolly Cobbold Classic. He did not progress past the Semi-Final group at the 1983 International Masters, but won the 1983 Irish Masters with an impressive 9-2 win over Ray Reardon.

The 1983 World Championships was a rout. Rex Williams was dispatched 10-4. Dennis Taylor put up a fight, but succumbed 13-11. Eddie Charlton was thrashed 13-5. Defending Champion Alex Higgins was destroyed 16-5. In the final, Cliff Thorburn was dominated 18-6. Steve Davis was back on top of the world, and there wasn’t any doubt about it.

Snooker through the Ages – 1981/82

The 1981/82 season had a total of 73 players, up from 63 the previous year.

There were 32 active players, and their final ratings based solely on their performances in this season were as follows:

The best player was Steve Davis, for the second season in a row. He had a blistering start to the season. He won the 1981 International Open, reached the semi final of the 1981 Scottish Masters, reached the final of the 1981 Northern Ireland Classic, won the 1981 UK Championship, won the 1982 Pot Black, reached the final of the 1982 Classic, won the 1982 Masters, won the 1982 Tolly Cobbold Classic, won the 1982 International Masters, reached the final of the 1982 Irish Masters, then reached the semi-final of the 1982 Highland Masters.

It was no surprise, therefore, that he reached the 1982 World Championships as a huge favourite to defend his title. However, he crashed out in a shock 10-1 loss to Tony Knowles in the first round. In a reversal from the previous season, he won the final event of the season, the 1982 Pontins Professional, finishing a massively successful season with a win, and the number 1 spot with a score of 1212. The world title, however, had eluded him.

To say that Alex Higgins was an unlikely World Champion is an understatement. He entered the tournament as the #11 seed, 10 years after he last won the event. He had ranked 9th in my rankings the previous season, and in his own words was having the “worst season of my professional career”. He had failed to progress past the semi-finals in every major event, and excluding the World Championships had lost more frames than he had won across the season. At the Crucible, he started with a relatively easy draw against Jim Meadowcroft, who he beat 10-5. He then faced a tougher opponent in the form of Doug Mountjoy, and squeaked through 13-12 in a decider.

Progressing to the quarter finals, he played Willie Thorne, beating him 13-10. In the semi-final he faced a young Jimmy White, and was trailing 15-13 when he made 3 successive half-centuries to win 16-15. His break to level the match was a potting masterclass, where the white ball was rarely under control but he managed to pot his way out of trouble and clear the table. The World Final against Ray Reardon was another close game, and stood at 15-15 before Higgins found his form and won 3 successive frames to win the title for a second time.

This win helped Higgins maintain a good rating of 1039, but due to the improvement of other players he fell from 5th to 6th in my rankings. He was, however, World Champion once again.

Snooker through the Ages – 1980/81

The 1980/81 season had a total of 63 players. To be listed in my rankings, players must be “active”, which I define as having either played at least 10 matches, or having reached the semi-finals of the World Championships. However, all players are included when calculating the player ratings.

There were 19 active players, and their final ratings based solely on their performances in this season were as follows:

The best player was Steve Davis. He started the season relatively poorly, losing 9-2 to Terry Griffiths in the quarter final of the 1980 Canadian Open in August, then failing to win his group in the 1980 Champion Of Champions in October. His first tournament win of the season, and of his professional career, came in the 1980 UK Championship, where he beat Tony Meo 9-5, Terry Griffiths 9-0 and Alex Higgins 16-6 to win the November event. He followed up on this in the following month by winning the 1980 Classic, with wins over Cliff Thorburn, David Taylor and Dennis Taylor.

A bad spell followed. He was out of luck in the single-frame 1981 Pot Black event, losing all his matches, and lost 5-3 to Perrie Mans in the first round of the Masters. He did not participate in the 1981 Tolly Cobbold Classic, and lost 4-2 to Ray Reardon in the Quarter Final of the 1981 Irish Masters.

In March, Davis found his form, winning the 1981 Yamaha Organs Trophy and the 1981 English Professional Championship in quick succession. He carried this good form into April, and went into the World Championships as the favourite with the bookies, despite being seeded 13th.

In Sheffield, he met Jimmy White in the first round, winning 10-8. He met Alex Higgins in the second round, winning 13-8. In the quarter final he played Terry Griffiths, winning 13-9. The semi final was against the reigning champion and number 1 seed Cliff Thorburn. In a bad tempered match, during which Thorburn took umbrage at Davis’ offered handshake when 57 ahead with the pink and black still remaining, David emerged victorious 16-10. The final was against Doug Mountjoy, also in his first World Final. David took an early lead, and stayed ahead throughout, emerging as World Champion with an 18-12 victory.

A first round loss to Terry Griffiths in the 1981 Pontins Professional was of little importance after the win at the Crucible, and he finished the season as the #1 player in the world, with a rating of 1212.

Snooker through the Ages – Introduction

I have developed a method of ranking snooker players, which I will attempt to explain here. I will then write a series of posts which cover the long history of snooker, ranking players each season and comparing players over time.

No method is perfect, and my method isn’t either. Nevertheless, the results do seem to make sense, and I hope it is as interesting to read about as it was to develop.

The starting point is the basis of most rating systems, which is that every player has a score denoting their skill level. The difference in scores between 2 players can be converted into a chance of winning a given match. I have used the same scale as used by the Elo system, where a player with a 200 point advantage should win around 75% of their frames, and a player with a 400 point advantage should win around 90%.

For the purposes of this exercise, I assume that every player has a fixed rating for any given season, which does not change during the year.

The method I have used is as follows:

Let’s take a best of 19 match between 2 players. We don’t know anything about their abilities yet, so let’s assume they both have a rating of 1000.

If Player 1 wins the match 10-4, he has won 71% of the frames played. Given the scale I have used, we would expect a player to win 71% of frames against a player with 159 fewer points.

We can therefore approximate the ratings of the 2 players, by placing them 159 points apart, with the midpoint being the average of their previously estimated scores (1000).

That gives us estimated ratings of Player 1 (1079.50) and Player 2 (920.50).

As the lengths of snooker matches vary, I give these estimated ratings a weighting based on the length of the match, with best-of-19 or above having a weighting of 1, best of 3 being 3/19^ths, best of 5 being 5/19^ths, etc.

If this calculation is done for every match in a season, and the weighted average is taken for each player, we have an estimated rating for each player.

Of course, these ratings are not great. Because we started assuming every player had a rating of 1000, the initial output is better than nothing, but fairly naïve as it doesn’t reward wins over good opponents or punish losses to weaker players.

Thankfully, we can repeat the process, but instead of using 1000 as the inputs, we use the ratings we have just calculated. This then becomes an iterative process, with the output being fed back in over and over again until the ratings converge on a settled result.

We can see that the estimates are improving by calculating the difference between the ratings and the estimated ratings for each match, taking a weighted average, and seeing this reduce with each iteration of the system. Eventually, the error stops reducing. At this point, the error has been minimised, and we have our final ratings for each player in that season.

In themselves, these ratings are only useful in a relative sense, in that the differences between players tell us something, but a rating of 1300 doesn’t really mean anything.

Ideally, we will have a standard against which all ratings can be judged. In my method, I have moved all the ratings in the 1980-81 season, so that the average of the top 16 players is 1000.

In all other seasons, I have first calculated the difference between all the players, and then placed these on the scale in such a way that the differences between the ratings of established players in successive seasons is minimised. This allows all ratings in all years to be seen on the same scale.

In my next post, I will review the 1980-81 snooker season, and calculate the ratings for that year.

UPDATE:

Having reviewed the rankings produced by the above method, I have made 2 changes.

Firstly, the weighting for the estimated ratings now include a preference for players with more matches played, so it is not as easy to get a high rating by beating players with few matches.

Secondly, snooker players play to win matches, not just to maximise frames won. To account for this, if a player wins 60% of his frames, I will give a score of 80% (The average of 100% for a win, and 60% for the frames won). If a player wins 20% of his frames, I will give him a score of 10% (The average of 0% for a loss, and 20% for the frames won).

I find this produces ratings which seem better than the initial version.