Rankings and blowouts

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The S curve seems to be working as a system - the 12 teams going to Champs this year are ranked 1 through 12 in the WFTDA rankings. This should please people because one of the criticisms pointed at regionals was that the best teams didn't necessarily go to champs - particularly in the case of the Westerns where only 3 of the 'big 6' could ever qualify. (Indeed this year 5 of the west's big 6 are going, the one exception being Rat City). However, with the new ranking system has come a new problem - or rather, a massively increased version of an old problem. The number of blow outs is increasing. Dramatically. Why? Well there's generally two types of ranking systems, one based around wins and losses, the other based around relative performance. When I ran the unofficial UK rankings I used the ELO system (the one they use for chess). That system is entirely based on getting points based on wins and losses. It works on a system of a 32 point spread. So, for example, if two teams at the same ranking play, the team that wins gains 16 points, the team that loses, drops 32 points). A higher ranked team gets fewer points from beating a lower ranked team and the bigger the gap between the two, the fewer points that the higher ranked team would get if they win and the more they drop if they lose. (Eg a team may gain 4 points if they win, but drop 28 if they lose). The downside to this system is that if, say, Croydon Roller Derby lost to Gotham by 1 point, they would still lose ranking points despite putting in a performance that should see them rocket up the rankings. With an ELO system the point spread doesn't matter, just the outcome. With performance based rankings - like the current WFTDA one (which can be found at http://wftda.com/files/wftda-rankings-calculator.pdf), it's the other way around; it's all about the points spread rather than the outcome. So with this system you can win a game and drop in rankings if your performance is below what is expected - and performance is measured purely by the ratio of points scored. So, with our hypothetical game above, Gotham would lose a hatful of ranking points at the expense of Croydon. The down side of this system is that games obviously become points driven. 

It also means that if you have a region where all the teams have low rankings (and this is the cause of why almost every European team is under-ranked) it is impossible for them to climb up the rankings table because even if you batter any and all opposition the lower the starting ranking position the harder it is to climb the rungs. And, because teams are aware of this, it makes rankings conscious US teams less willing to play European teams. It's also causes problems when you have teams that split as they effectively become a new team with a low ranking. Team United are massively under-ranked and find it extremely hard to find sanctioned games because everyone knows they are massively under-ranked being, as they are, 90% of the now defunct Mid Iowa Rollers who were a top 50 team. 


Neither system is perfect, for sure, and each system has its flaws - which is why most professional sports use simple round robin league tables. However, in the WFTDA not all games are equal, at least in terms of rankings. If you think that point spread is important for teams, it's even more so for the teams in the top 60 because of divisionals ranking multipliers.   

Here is the table for rankings multipliers. 
Game Type Value
Regular Season 1
Division 2 Qualifying 1.15
Division 2 Consolation Bracket 1.15
Division 2 Elimination Bracket 1.25
Division 2 Third Place (Champs) 1.25
Division 2 Final (Champs) 1.35
Division 1 Qualifying 1.25
Division 1 Consolation Bracket 1.25
Division 1 Elimination Bracket 1.35
Division 1 Championship 1.50

Given the above, it actually makes blow outs even more likely at divisional play because, for example, in a D1 qualifying game, there's a bonus 25% ranking points available which makes each point even more important. So say for example KCRW play No Coast and then play them again in D1 qualifying game and that the scores are exactly the same in both games. Because the second game was at a divisionals, there's a 25% bonus/penalty to the winning/losing team. This obviously affects the way that teams are going to play because rankings are so important when it comes to the next season's rankings for divisionals which leads to more blow outs. The average winning margin at this year's four divisional games was 122.8 points*. That's a lot of blow outs (and the stats would have been even worse had it not been for Salt Lake City). 

The net upshot of this is that there is no mileage (at least for the higher ranked team in a game) in there being a close game. Fielding a weakened team or testing a slew of new skaters actually - for rankings purposes - hurts the team in terms of ranking points because the way that the rankings are set up, every point scored means ranking points gained or lost. And if you think that is problematic in the US, consider teams like Victorian and London who basically cannot play sanctioned games against teams from their own countries because the rankings gap means that they have to win by ridiculous numbers just to stop from losing, let alone gain, ranking points. In the case of London this means we have the counter-intuitive situation where they either have to travel to the US or get American teams to come to the UK for sanctioning purposes! 

This leads to a real push-me-pull-you in terms of derby in that people like the rankings, but they don't like blow outs. Unfortunately one is a consequence of the other. 


*According to my notoriously shaky math. Any mistakes in this figure are entirely down to my own poor math skills and please feel free to fix my figures if they are incorrect. 

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DOB: 11/27/1968
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DERBY TODAY
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