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Monday, 30 November 2015

The Alternative EPL Table, Iteration Number One.

In A Galaxy Far, Far Away.........................


Week 14 of the current season ended in a 2-1 defeat for the league leaders, Arsenal, in a game of few chances at Norwich. They spurned the opportunity to extend their lead over Manchester City who went down by the odd goal in a five goal thriller at home to Southampton on Saturday.

Spurs heaped more pain on defending champions, Chelsea, winning comfortably, 2-0. Chelsea are now beginning to become cut adrift at the foot of the table along with Newcastle, who rode their luck in a goalless draw with Palace.

Former manager of the year, Tony Pulis further enhanced his reputation by keeping his WBA team in the top four after a 1-1 draw with near rivals WHU.

Fallen giants, Liverpool and Manchester United, each recorded narrow 1-0 wins against Swansea and Leicester, respectively, but still remain detached from the title race.

Gary Monk's Swansea's league position continues to spotlight the talents of their young exciting manager, while Leicester, as predicted are struggling to emulate their strong finish last season and just stay clear of the relegation positions under Claudio Ranieri.

Stoke played half a game with ten men.

The Premier League, sponsored by Random Shot Based Simulations Inc.

Sunday, 29 November 2015

The Table Often Lies.

The group phase of the Champions League is cleverly designed to maintain interest to the end of match day six.

The winners of the group are seeded to meet the runners up from the other groups, subject to a restriction that prevents a team playing another from the same country.

The third placed teams become the favourites to lift the Europa League and the fourth placed teams get to spend more quality time with their families.

Group
Team
% To Win Group
% To Qualify 
% To Drop into Europa League
Median Points
Total
E
Barcelona
85
97
2
14
E
Roma
9
55
34
8
E
Bayer Leverkusen
6
40
40
7
E
BATE Borisov
1
8
23
4

So even if one team is strongly favoured to win the group, there is likely much to play for over the full course of the twelve games.

Group E was the easiest to predict the most likely winner. Top ranked Spanish Champions League representatives are generally superior to second ranked Serie A teams, who in turn are superior to below average German qualifiers. Each of which are superior to a champion from Belarus.

My pre tournament estimation of the chances of each team filling a particular spot for Pinnacle can be seen in the table above.

Others took a slightly more optimistic view of the chances of Bayer Leverkusen and a typical average points expectation based on reported odds was an average of 13.5 points for Barcelona, 9 for Bayer Leverkusen, 8 for Roma and 3 for BATE Borisov.

Already we have a dilemma in deciding if finishing position fully reflects talent. Namely, opinions differ as to who is the best to start with and the argument begins to become circular.

If we again treat the bookmaking odds as all seeing and able to perfectly capture the true chances of each side in each individual group match, it would be useful to know how often the teams finish in the order predicted by the bookmaking.

36% of Group E simulations finish with Barca as top seed, Leverkusen as runner up, Roma as Europa League bound and BATE going home where each team plays six matches.

If we double the tournament length so that each team plays twelve rather than six games, a finishing order that reflects the odds we've used in the simulations is still less than a 50% chance.

Quadrupling the length of the group stage to 24 matches per team produces the desired order to reflect talent just over 60% of the time.

Should you wish to trade increasing certainty for viewer indifference, a 96 game per team schedule pushes to beyond 77% the percentage of iterations with Barca as seeded knockout stage entrants, followed by Leverkusen and Roma Europa League bound.

Competitions must strike a balance to reward talent (to please the participants) and maintain a degree of uncertainty (to enthrall the audience), while sticking to a manageable time frame.

So in the real world, especially where teams are closely matched, the table often lies.

Saturday, 28 November 2015

Who is the Best Team in Group D?

The Uefa Champions League Groups are concluded in early December and the list of already qualified teams is a familiar mix of Spanish, German, French and English teams.

Seeding and a six game, home and away league format attempts to ensure the best sides progress and aren't caught out in a single knockout match,

Group D appeared one of the most competitive prior to match day one, containing a representative of the four major European countries, in Juventus, Manchester City, Sevilla and Borussia Moenchengladbach.

Juve and City had already qualified after match day four, with the former holding a two point lead going into match day six. Bookmaking odds had favoured Manchester City to top the group, although in a preview written for Pinnacle, I suggested that Juventus should be considered the more likely group topping side.

So it is tempting to claim that my assessment of the two sides was well founded.

However, although the runner up from last season currently head the group, they are merely odds on to top it after the final reckoning, so City may still justify pre tournament, group favouritism.

There is also a significant possibility that City may be superior to Juve, but still finish below them after just six home and away, round robin games.

The bookmaker's assessment of each of the four teams can be broadly demonstrated by converting the match odds into expected group points. City were expected to gain an average of 10.3 points compared to 9.6 for Juve, with Sevilla and Moenchengladbach trailing with 8.4 and 4.9 points, respectively.

More usefully, simulating the group using the same bookmaking odds that favoured City results in the English team topping the table 45% of the time compared to 35%, 15% and 5% for the respective remaining three teams.

So City may be the best side in the group, but it is more likely that someone else would top the table if they play just six group stage matches.

Therefore, the books may claim to have been correct, but randomness may still overcome their best predictions after match day six.

If we extend the group stage fourfold so that each team plays 24 matches, the separation between the current top two and the others increases.

Juve now win the group 33% of the time and City become slightly more likely than not to top the group. Sevilla has a 9% of winning and Moenchengladbach is relegated to the realms of improbable, but not quite impossible.

If we become even more extravagant and condemn each team to play 96 group games based on bookmaker's odds, City are now a 74% chance to top the group, Juve 25% with the other two teams a virtual probabilistic irrelevance.

Even turning a four team group into a weekly event spread over nearly two years, there is still a one in four chance that the best team doesn't win the group when two of the teams are closely matched.

Therefore, declaring one team superior to another, even based on a 38 game Premier League season almost certainly fails to account for a set of trials that are awash with randomness and similarly comparing players based on a paltry amount of data, often without context is likely to be equally misleading.

League position = talent + randomness.