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Showing posts from September, 2017

Points vs Expected Points: Gameweek 6

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Elite forwards It was quite a week for the league's leading forwards with five of the seven 10 million pound men all finding the back of the net at least once (the other two - Jesus and Zlatan - were not in action). Kane owners were feeling smug after his 13 point haul in the early game, only for him to be eclipsed by Morata and almost matched by Aguero later in the day, while Lacazette sent a reminder to the league that he is another talented option with a brace on Monday night. There is an emerging theory that one must  own three of these elite options, and make up the difference elsewhere in your team with reasonably priced defenders and budget midfield options. While I understand this logic, I would not be so fast to dismiss the midfield elite with Sanchez and Hazard returning to their sides and the likes of Eriksen and Salah putting in quality performances every week. The wisdom of this argument will likely only be settled with hindsight. What we can review is which

Player share of key stats, by team

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The below visualization shows the share of their team's shots inside the box (SiB) and created chances (CC) each player have accounted for this season. The share represents only the games when the player was on the field so as to not penalise them for missing games. This also therefore means that the total team percentage will not add up to 100%. While shots inside the box are generally more valuable than those from outside, this data does not control for quality beyond that, so an overly trigger happy player like Andy Carroll might appear more valuable than he is, while a clinical finisher like Aguero might be underrated. Still, the idea here is provide a quick sense check as to where players rank within their respective teams. We often see people cite team A's superior fixtures to team B as the key reason to select player A over player B, but this misses the impact of the likelihood of these players benefiting from their team's favourable fixtures, which I hope this p

Elite forwards: a response to City's past week

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Over an eight day period last week, Man City thumped their three opponents by a combined score of 15-0, with Liverpool, Feyenoord and Watford unable to contend with Guardiola's men. It goes without saying that City were extremely impressive in these games and fantasy football managers are obviously taking note with Aguero and Jesus shooting to the top of many managers' transfer target lists (at the time of writing some 440,000 managers had already brought in Aguero and another 90,000 have targeted Jesus). The point of this post is not to suggest that these transfers are incorrect - indeed I might follow suit myself - but I did want to run over a few facts to maybe turn the temperature down on the need to make these moves right now. The chart below shows the expected points each of the listed elite forwards have registered through the first 5 gameweeks. You can see Aguero's terrific GW5 effort eclipsing his rivals this past week but you will also note that Kane has three

Gameweek 5 Projection

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Note: I have still not figured out a method to allocate clean sheet points to players that I'm happy with, so for now the below projection is for attacking points only (plus two for playing time). Clean sheet forecasts can be found in the team projections here .

Revised player forecast

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One of the key complications with player forecasting - or indeed I imagine any forecasting - is deciding which data set to use. When it comes to fantasy football, we obviously want to include as much recent data as possible but the issue is when we can exclusively rely on this season's data and when we need to look to the past seasons for guidance. I am generally quite happy to solely rely on this season's raw event data such as shots or created chances fairly early on as they tend to occur with relative frequency and thus stabilise in a short time frame. How these events get converted into goals can fluctuate a lot more though, as the key driver there - goals - happen much less frequently. With this mind, the revised player projection table below allows you to choose how you are converting the raw chances into goals and assists: Past season - uses the benefit of having a 38 game sample to see how different teams convert chances into goals. The negative, of course, is that te

Expected goals, assists and points

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The visualization below plots the expected fantasy points arising from expected goals versus those arising from expected assists. The idea here is that this is a quick snapshot of how a player has performed to date and where their points are coming from. It should be noted that xG and xA numbers used to generate the xP are based on shot, created chance and possession date for the 2017-18 season only but the conversion rates to convert those raw events into goals are regressed using team and league rates for both the current and prior seasons. I hope this eliminates some noise from the small sample sizes of the early season but it's still worth noting that this is a snapshot based on three games so should act as a data point for your transfer assessments but not an all encompassing answer.