Wednesday, September 27, 2017

Points vs Expected Points: Gameweek 6


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 of the elite forwards should be targeted. While Morata stole the headlines, it was actually Aguero (and to an extent Lacazette who benefited from a penalty) who led the week in xP. This was perhaps to be expected given Aguero's opponent but it served as a welcome reminder that all else being equal, Aguero still likely has the potential for the most explosive points totals given the heights this City team have shown they can hit. However, the Argentine is also the most likely player in this elite group to be rotated and of course costs over a million more than Morata, Jesus and Lacazette.

Through the next 12 gameweeks the model still has Kane as a clear leader followed by Lukaku and Aguero in a near tie. Jesus and Morata are then closer behind with Lacazette trailing by some distance. There's talent there for sure but given the Arsenal man's price tag, it's almost impossible to justify taking that flyer right now. One element that intrigues me about Morata is the share of Chelsea's shots inside the box he's accounted for when on the pitch (30%). No one else in the Chelsea team is over 16% which makes you feel very confident that if Chelsea have a weak opponent and the Spaniard plays, fantasy points are likely to come your way. The same cannot always be said for someone like Aguero who not only faces increased rotation risk but also has to share the spoils with more players when he is on the field (22% of SiB). Of course, if City keep scoring 5 and 6 goals a week there will be plenty of goals for everyone but when the scoring machine slows a little, one could argue that Kane (41% SiB), Morata and Lukaku (31% SiB) offer great certainty of success. In short, I believe Kane is close to a must own but could make an argument for any of the other group and wouldn't be scrambling and spending 4 point hits to flip between them regularly.

Mid-level forwards
For those not yet convinced by the three-elite forward option, a few players this week highlighted their own potential to round out your front line. Vardy and Hernandez have both been steady performers this season and while they certainly aren't unknowns (12% and 20% ownership respectively), they are sometimes forgotten men when compared to the elite group.

I think it's too early to make a call on Bony yet, but there is a lot to like with Vardy and Hernandez. The problem is not so much these players, it's who they would be paired with. Presumably the rationale for downgrading from, say, Kane to Vardy would be to free up funds to use in midfield but of the top ten most expensive midfielders I would suggest that only Salah and Eriksen have been definite successes to date. If Hazard and Sanchez can return to form then they could offer just as much value as the elite forwards and thus a cheaper forward would be a useful, possibly essential, tool to give you access to them but until that happens it is indeed looking like the best bet might be to roll with three elite options.

An alternative idea is to go with just two truly elite options and then stack your team with a host of second tier priced players such as Silva, Mkhitaryan, Pogba, Vardy and even the likes of Sterling and Sane (see below). This protects you somewhat from rotation and makes it easy to change direction during the season, though the captains armband becomes tougher to award and if you structure your team without someone like Kane, it can take two or even three transfers to free up the funds to get him back, so you better be sure you're happy with the direction (or have a wildcard to spare).

Man City midfielders
Generally a prerequisite for fantasy consideration is being all but locked into a team's first team plans. Of course we know that the likes of Kane will still be dropped every now and then but we don't tend to tolerate fringe players who might only get 20-25 starts. Enter Sterling and Sane. The City pair rank 6th and 8th in points among midfielders and generally have the underlying stats to support their impressive hauls.

At just 7.8m and 8.3m they are competing with mid-level options like Antonio, Sigurdsson, Pogba, Rooney, Benteke or Defoe and when playing, their advanced positions in such a dynamic team will surely help them eclipse this group. Though perhaps slightly more impressive when playing, Sane's lack of Premier League experience and numerous sub-appearances still make me nervous but I am convinced that the criminally underrated Sterling will get enough time to make him valuable. You will need to secure strong bench options though - which might therefore preclude you owning three elite forwards - but I definitely think there's a way to fit him into your side and offer a very reasonably priced way to get access to this talented City side.

 After this week's trip to Chelsea, City's fixtures are extremely promising and I would definitely consider having Sterling for 9/12 of them rather than many of the above group for 11/12 of their games.

Monday, September 25, 2017

Player share of key stats, by team

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 player share data can help with a bit.

Tuesday, September 19, 2017

Elite forwards: a response to City's past week

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 gameweeks with an expected points total close or above Aguero's game against Watford. Now, it should be noted here that the expected points number I am using is not as complex as some models, and indeed is a simplified version of my own, but it does a good enough job highlighting that Kane and Lukaku have been wracking up very solid shot and created chance numbers on week-on-week and so one very good game from Aguero, and to a lesser extent Jesus, does not need to completely change your transfer plans.

Note: Firmino's sky high xP in GW1 is due to his penalty which is scored in the model as essentially 4 guaranteed points on top of his other goal and assist potential.

The model forecast still likes Kane quite a bit more than any other forward using the blended or prior year season conversion rates, which ranks Lukaku just ahead of Jesus and Aguero in terms of projected goals. Aguero tops all his rivals when it comes to assist threat which is a useful tool to have and would push him sufficiently far ahead of Jesus as to justify the extra million or so pounds.

To me, there remains a relatively clear hierarchy of Kane at the top, Lukaku and Aguero in a near tie for second and then Jesus, Morata and to an extent Firmino following in the lower tier. Therefore the switch from Lukaku to Aguero makes good sense but is not suddenly a "must do" transaction if there are other areas of the team you need to address.

Friday, September 15, 2017

Gameweek 5 Projection

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.

Friday, September 8, 2017

Revised player forecast

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 teams have changed since the previous season, both in terms of personnel and with the arrival of three new promoted teams (who use a historical average for promoted sides in this forecast);
  • Current season - the most up-to-date conversion rates will help to spot players and teams who have genuinely improved since last season but will be subject to a much greater sample size risk so will kick out some unusual results;
  • Blended - this rate uses a combination of historic and current data, increasingly weighted towards the latter as the season progresses.
A couple of highlights below that jump out as of gameweek 4:
  • I generally dislike the term "must own" as there are thousands of ways to build a successful team but there is no denying that Kane's data so far this season is simply incredible. The fact that his ownership percentage has fallen to 26% - including a 0.1m price reduction - represents a great opportunity and it's hard to see how one could select a wildcard team now without the Spurs man.
  • Mahrez is an interesting case of low ownership with just 5% of managers fancying the former Champion. Perhaps this was due to the presumption he would leave Leicester during the transfer window, but now that is closed, a lot more attention needs to be directed his way. Using the prior season conversion rate cuts his xG significantly which reflects the fact that Leicester have been so clinical (lucky?) this term, but nevertheless he remains a legitimate elite midfielder who at 8.5m isn't too badly priced.
  • The xA listing offers more moderately priced options than the xG list, which makes me wonder if it will be better to focus resources on elite forwards and midfielders who can score goals, knowing that you can find low-risk-high-reward midfielder picks who contribute assists with cheaper options like Brady, Carroll or Loftus-Cheek.
  • With Spurs offering about as good defensive prospects as any team, the fact that Ben Davies ranks so highly in xA while also being cheaper than most of his teammates makes him a very promising prospect.

Select tabs below for goal and assist forecasts for the next 6 and 12 gameweeks:

Saturday, September 2, 2017

Expected goals, assists and points

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.