Cricket Performance Ratings - Opinions seeked

Thanks

this is so hard.

it's an idea i've been mulling over for some time as well.

i'm not suggesting that it's impossible to improve on the current way the data is analysed and compiled to provide better indicators of performance, but i still think that data alone isn't enough.

my problem is that so often the nature of dismissal as well as missed chances and unrewarded spells can all only be compiled from watching a match. and that batting is as dependent on the quality of the bowling as it is on a batsman's skill. I noticed you gave Brathwaite a high rating in the world t20 final, but what choice did he have, and how awful was Stokes' decision making. I couldn't give Brathwaite any more than a third of the rating points I would award Kohli for his semi final knock against Australia. I find that a huge factor in t20. **** or bust situations regularly present themselves and there will always be a risk that noise is mistaken for achievement.

i came to the conclusion that you'd need knowledgeable cricket fans, familiar with cognitive biases, to amend a technically derived score (the structure of which they understood) at the end of each match, and you'd need to keep an audit of amendment process to ensuring consistency.

Very interesting post DS. I think all you really have are the data. Yes, there is a lot of noise and some serious sample size issues but as you clearly know and imply, there's no objective or reliable way of analysing performance otherwise. Clearly it is important to understand the limitations of the method used though.

The T20I thing is also interesting. I don't rate the ratings for them at all, because there are so few games played. The guys at the top might be the best players but I don't think there's much more than a vague tendency towards having any real idea. As you say, frog2, looking at league games with a far bigger sample size is probably more sensible but even then you're assessing a rather random format.

If I'm reading your ratings correctly then some of the T20 League batting ratings look miles out to me (they're the only ones I've looked at so far). The top ranked players seem reasonable but as you go down the rankings then they seem to deteriorate.

Chris Broad ranked at 68 with so many good batsmen rated below him e.g. Bairstow ranked 99, Stokes 106, Hales 156, Faf 198, Root 220. Common sense tells us that something's deeply wrong with these.

higher than Sam

Initial thoughts were that combining data from different leagues is quite difficult as not all leagues are equal.

Apologies will poster later as watching footy now.

Half-time in footy.

You're covering quite a lot of things very quickly here and need to think about them.

Another early thought I had is what would you do with the ratings? Horse ratings I can see as used to do my own speed ratings for AW meetings only. That was initially why I joined Betfair.

If you had two teams where one team had better ratings for every player than the other then I'm not at all certain that I would back that team. Odds, whose batting first, pitch, weather, need to win, recent form, individual match ups, etc, so many other things to consider than just player ratings.

Not trying to be negative just throwing some thoughts onto the pitch.

As mentioned you have a sample size issue. In addition, the majority of dismissals are caught which is beyond the control of the bowler (as are stumpings and runouts). Dollies are dropped and crackers are taken. And edges behind sometimes hit the stumps and sometimes go for boundaries. In combination, these factors will give a biased picture of both bowling and batting proficiency. What I would like to see is a weighting for how good dismissal chances are irrespective of whether they are taken or not. Although I suspect that is too difficult.

You say you use a Neural Network, but don't say how. What does a NN give you over a simple summing and averaging of individual players performance?

Otherwise, I'd say you are on the right track, and it would be good enough to give you a betting edge. How much of an edge I can't say.

The NN also gives the chance to set the target value when building the model so you get a win probability from it. With averaging you just have, say, Team 1 rating 42, Team 2 rating 25. But what should the odds be?

How much value are you awarding for "winning" a game? Only I think I'd give roughly equal weighting to a guy getting 30 off 12 setting a total that happened to get overhauled off the last ball versus the same game where the final ball was a dot rather than a 4 so the defending team won. The Braithwaite innings getting that many points smacks a bit of results merchantry. What matters in terms of prediction for future games is the skill that was displayed (as far as you can fathom that from what happened in a match, which may not be all that far), I think, rather than the eventual match outcome. You say something similar about Kohli not winning the IPL but as one of 22 players on the pitch each time, I don't think that's the way you'd work out how good he is.

Just another quick observation. On your T20I batting rankings you have Afghans ranked 6 and 7, a Hong Konger at 9 and a Jock at 15. If you ask anyone to name their best twenty T20I batsmen I doubt if they would include those players. I imagine that the NN doesn't take in to account the strength of the opposition so high rankings can be achieved by performing well against relatively weak opponents.

Fatslogger,

From what I can make out the machine is doing it does not rate first innings performances on the final result. Scoring 30 off 12 balls in exactly the same situation in the first innings would get the same rating regardless if the team beating second won of lost.

Batting second it would be dependent on keeping up with the required rate and getting the team across the line.

Is there a difference in the inputs to the net depending on whether it's say a T20I or a T20 league game?

Very useful feedback. A fair bit of revision is needed to iron out the flaws.

Presumably the players are some of the inputs? For a T20I if you only have one set of player rankings (as you currently do) then surely associate team players will be overrated when playing against a top team?

If you aggregate each team's players (maybe just a simple sum) does the aggregate correlate with the Team's Ranking?

To your last post. Yes. That is how they are calculated at the moment just using the individual players. Yes on the rare occassion like a world t20 when associates play full teams it would not make sense.

Have only looked at T20 so far!

Does DL screw things up?

Debut some as for horseracing I used have one input as 0 for debut and 1 for not debut.