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Showing posts from October, 2012

Dousing the fire, fanning the flames: Gameweek 9

You know the story by now; each player has been assigned a 'Buy', "Hold' or 'Sell' status. These don't necessarily reflect what I would do, more what I believe to be a reasonable action at this time: Buy - the player can be purchased immediately taking consideration of his playing time, fixtures, injury status etc. This status does not necessarily mean you should buy him now as it depends who else you own, only that it is reasonable to do so. Hold, and/or monitor - if you own the player you're not in a rush to ditch him but there's sufficient risk here to justify potential buyers holding off. Sell - the player has too many risks and should either be sold or not purchased. This does not mean he might not have value in the future, just not right now. Robin Van Persie 12 points I was initially reluctant to throw a 'buy' tag on van Persie because (a) the formation issues his arrival caused at Old Trafford and (b) his massive price ta

Individual forecasts: Historic player data

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One of the issues of the new forecast model is deciding which kind of shots to use to forecast player success: all of them, only those in the box or only those on target. Those on target have the best correlation to goals scored, however, there is a slight concern with limiting ourselves to that data alone. Consider the below example: Robin van Persie: Appearances 10, Total Shots 55, 10 Shots On Target, 3 Goals If we only look at his shots on target we see that he is averaging just one a game, with 30% of them hitting the back of the net. The issue is that he has historically hit the target at a much better rate than 10/55 (18%), having a success rate more in the 44% range. We therefore need to adjust for the fact that we believe 24 of his next 55 shots (44%) will hit the target and thus his expected goals will be higher. We have some issue about how to generate this historic rate, especially with regards to what data to use, but for now I'm happy to look at such data for pl

Lineup Lessons: Gameweek 9

Arsenal Mannone, Sagna, Mertesacker, Vermaelen, Andre Santos, Arteta, Wilshere, Cazorla, Ramsey, Podolski, Giroud Subs: Martinez, Koscielny, Walcott, Coquelin, Arshavin, Jenkinson, Gervinho Poor old Jenkinson made way for Sagna who has finally shaken off his injuries. Jenkinson did a very good job while deputising for the French full back but for the overall value of the team Sagna probably gives them a decent boost at both ends of the pitch. The downside, of course, is that we lose one of the safe and cheap ways to access this unit. If Mannone can continue to hold of Szczesny when he returns to fitness he would be the obvious pick, though a lot of managers are hesitant to use too many transfers tinkering with 'keepers who might not always play. Mertesacker still faces some competition from Koscielny but he appears to be fairly safe for now and would be my pick for Jenkinson owners looking to move on. Gibbs should be back soon so the left back spot is still up in the air. Wi

Medium Term Goal Forecast

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The mechanics of the new model were expanded on here , so check that out specific questions on how the below forecasts differ from the old goals based system (clue: the differences are varied and significant!). While the weekly forecast is more related to line-up decisions, the below chart should hopefully help with transfer decisions and longer term planning. Attacking Forecast Powered by Tableau Defensive Forecast Powered by Tableau Weekly Forecast  Predicted goals per game scored for the next eight gameweeks, based on shot data and team conversion rates Avg  Average goals per game forecast for the next eight gameweeks Gr  The percentage of 'green light' games over the next eight gameweeks, currently defined as a forecast goal tally equal or greater than two for attacking sides and less than one for defensive teams. Am  The percentage of 'amber' games over the next eight gameweeks, currently defined as a forecast goal tally between 1 and 2. Rd  

Gameweek 9 Preview

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This week's preview piece is going to be in two pieces. The first piece will be the actual forecast for the week and a very high level explanation of what the numbers mean. Lower down you'll find the mechanics behind the forecast along with some identified weaknesses and some proposed questions as to where we go next with the model. First then, here is this week's forecast: Powered by Tableau xG Shots Expected goals based on shot data for both the highlighted team and their opponent to date xG Shots Regressed Expected goals based on shot data for both teams, this team regressed using league average shot conversion rates. The Nuts and Bolts This is the end result of a project I've been working on for a couple of weeks now, and it was discussed at length in an earlier piece . Now the data has actually come together though, I wanted to take the opportunity to run through an example so as to (a) help everyone understand where I'm coming from and (b) I

Dousing the fire, fanning the flames: Gameweek 8

You know the story by now; each player has been assigned a 'Buy', "Hold' or 'Sell' status. These don't necessarily reflect what I would do, more what I believe to be a reasonable action at this time: Buy - the player can be purchased immediately taking consideration of his playing time, fixtures, injury status etc. This status does not necessarily mean you should buy him now as it depends who else you own, only that it is reasonable to do so. Hold, and/or monitor - if you own the player you're not in a rush to ditch him but there's sufficient risk here to justify potential buyers holding off. Sell - the player has too many risks and should either be sold or not purchased. This does not mean he might not have value in the future, just not right now. Juan Mata 18 points A couple of us on Twitter have been discussing Mata a lot these past couple of weeks (h/t to TalkOfTheCrowd for the original tip) and it seems I might have missed the boat bo

Lineup Lessons: Gameweek 8

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I didn't see a ton of football this week as I was away for the weekend so this week's lineup lessons will be somewhat condensed, focusing purely on surprise omissions and potential issues, and avoiding the often rambling detours these electronic pages have become synonymous with. Indeed, the reader may well find themselves wishing your humble blogger watched less  weekly action to keep future posts this short. Arsenal Mannone, Jenkinson, Mertesacker, Vermaelen, Andre Santos, Ramsey, Arteta, Cazorla, Gervinho, Giroud, Podolski Subs: Martinez, Wilshere, Oxlade-Chamberlain, Djourou, Coquelin, Arshavin, Gnabry Nothing to report here at all. Wilshere made a return to the bench from injury (delighted for him: one of the English players with truly elite upside in my humble opinion), but from a fantasy perspective we're along from that mattering. This was an odd result for Arsenal, though not totally out of character with their recent struggles, and Cazorla and Podolski owne

Gameweek 8 Preview 2.0

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I am away this weekend so I'm not going to have time to write up how  the below numbers have been generated, but it's essentially the format prescribed in the recent goals and assist pieces, only limited to teams for now. I'm posting the data now so we will have a real test set of data from this weekend to work with, which will hopefully highlight a couple of areas where the model could be improved (and by that I mean where the process, rather than the result, is wrong. If Stoke hold United to no goals on 27 shots, the model isn't necessarily broken, it was just a bad day at the office for van Persie and co). xG Shots - expected goals scored based on the shot data they have registered and the shots given up by their opponents, regressed to a team average conversion rate (not a league average). xG Chances - expected goals scored based on the chances created by a given team and the chances surrendered by the opposition, regressed on a team average conversion rate