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1 month ago

Fanteam's Monster [GW38]: Goalkeeper Value Analysis

Football is not a high-scoring type of sport, meaning we don't have a privilege of multiple projections for each player to make our fantasy lifes much easier. Due to FanTeam's football scoring, goalkeepers is one position that is more prone to more or less accurate point projections compared to other positions. In this article, I go over the methodology to calculate saves numbers and potential value for each goalkeeper of the slate. If you find the math too heavy on you, just scroll down to the very bottom of the page for an easy-to-read chart that will help you pick the right goalkeeper based on your team composition.

 

Calculating Goalkeeper Projections

First of all, we have clean sheet odds, chances to concede 1.5+ goals and chances to win from bookies at our disposal. Also, there is a lot of useful information about saves, which is the most important aspect of Fanteam GK scoring (each save is worth 0.5 points).

I predict the number of saves for every goalkeeper in the slate based each team's game style and possible possession %. 

We can't just simply take the average number of saves for each goalkeeper and use it for every slate because there are different types of matches. Every team can play differently depending on the location, the opponent, form, etc., which can influence how many saves a goalkeeper is likely to make. 

This model for predicted saves is based on possession. If we correctly predict how a team is likely to play their next game, we can use the save data from previous matches that were similar in terms of possession. 

For my analysis I single out 3 possession categories:

• team has >55% possession;
• team has 45%-55% possession;
• team has <45% possession.

I predict possession percentages based on previous performances of the current season.

Now that we have a prediction of how each team is likely to perform against their current opponent, I also have to mention that it is football we are talking about.

Xhaka can get a red card in the 7th minute (lol, I hope it won't be an exact projection, because the Gooners will hate me for that) or Wolves can score an early goal and games will play out differently. We can't see into the future, but this method gives us enough grounds to try and predict the number of saves. 

Pred SoT MIN — a minimum number of predicted shots on target based on stats through this season 
Pred SoT MAX — a maximum number of predicted shots on target based on stats through this season 
Pred Goals — predicted goals based on bookie odds
PSoT-PG MIN  Pred SoT MIN - Pred Goals
PSoT-PG MAX — Pred SoT MAX - Pred Goals

I have analyzed the stats based on projected possession and taken the number of shots on target for each team just from the matches falling within the same possession category.

I've also considered the current form of each team and where the game is going to be played. In the next part of our analysis, I will look at opponent stats. 

Each shot on target can become a goal, so we should exclude predicted goals from this sheet, leaving us with just potential saves. 

If we're talking about predicted goals, it is based on bookies odds. When we subtract predicted goals from predicted shots on target, we get potential saves. Here we determined an attacking potential and we will go back to these numbers later, but now we have to analyze the defensive potential of each team.

Read more: GW38 Tactical Breakdown

Predicted Save MIN — a minimum number of predicted saves based on stats through this season 
Predicted Save MAX — a maximum number of predicted saves based on stats through this season 

I did the same thing with saves here. Selected matches with similar possession percentages played by a given team this season and looked at how many saves each goalkeeper had made in those.

Now that we have a range of predicted saves based on the team's defensive potential, let's do a little math and merge the two. 

PSoT-PG MIN  Pred SoT MIN - Pred Goals
PSoT-PG MAX — Pred SoT MAX - Pred Goals
Save MIN — a minimum number of predicted saves based on stats through this season
Save MAX — a maximum number of predicted saves based on stats through this season 
APS MIN — the average number between PSoT-PG MIN & Save MIN
APS MAX — the average number between PSoT-PG MAX & Save MAX

Let's look at the first row of the sheet above so that I can explain how it works. 

[1.82 - 4.82] is the predicted range of shots on target for ARS (EVE's opponent).
[3.00 - 5.00] is the predicted range of saves for Pickford.
[2.41 - 4.91] is the average between the two previous ranges and my final projection, where we consider the attacking potential of the 1st team and the defensive potential of the 2nd team.

If we put it simply, my calculations show that Pickford is likely 2 to 5 saves against Arsenal. 

Now let's take other aspects of GK scoring on Fanteam into account. 

Read more: Set-Pieces Analysis for GW38

CS (%) — chances to keep a clean sheet
FP (CS) — predicted Fantasy Points for a clean sheet (+4)
APS MIN — the average number between PSoT-PG MIN & Save MIN
APS MAX — the average number between PSoT-PG MAX & Save MAX
FP (APS MIN) — predicted Fantasy Points for Average Predicted Saves (MIN, +0.5 for each)
FP (APS MAX)  predicted Fantasy Points for Average Predicted Saves (MAX, +0.5 for each)
>1.5CG (%) — chances to concede more than 1.5 goals 
FP (CG) — predicted Fantasy Points for possbile conceded 1.5+ goals (-1 for each 2 CG)
WIN (%) — clean Sheet odds (+0.3 for win)
FP (WIN) — predicted Fantasy Points for possbile victory (+0.3)

Σ PFP MIN — a minimum sum of predicted Fantasy Points for goalkeeper
Σ PFP MAX — a maximum sum of predicted Fantasy Points for goalkeeper

These parameters include +2 points for 60+ minutes played as well. Please, remember that these numbers show us the probabilities for good/bad performances rather than exact fantasy points. 

Value MIN — ΣPFP MIN / Price
Value MAX — ΣPFP MAX / Price

My Picks

Avoid

Ederson, Mendy, Alisson, Lloris, Ramsdale. It's always better to pick defenders in such cases.

I would also stay away from the cheapest quartet this time. Jose Sa, Emi Martinez, Ben Foster and Angus Gunn are risking conceding a lot, according to their opponents' motivation and current defensive form. Aston Villa have the best chances to offer us  good value among all the cheap goalkeepers, in my opinion. That's why I would still consider Martinez if I don't have enough budget.

Southampton's defence is the one of the worst in the last 4 matches among all teams. Saints will play against Leicester away from home, so I really don't rate Alex McCarthy as a valuable pick. 

Leeds' motivation will be obviously high in the coming match, remembering their very possible relegation risk, but with their current form I think it will be so hard to keep a clean sheet this time. Brentford are in good form and I'm convinced they will score. Meslier's price is pretty high (7.5) so he's another pick to ignore for me.

Schmeichel (8.6) and de Gea (8.1) prices look bloody expensive because their chances to keep a clean sheet are just ~28% and their defensive form is far away from strong. 

Good Value 

Burnley are the 2nd team risking relegation, but I think they are in better circumstances than Leeds. They will play on home turf and their current form is stronger than Leeds'. I see Nick Pope (8.4) as one of the best options to keep a clean sheet among goalkeepers with average price.

I also deem Raya (7.7) as a valuable option, according to their good form and Leeds' problems.

If you enter multiple line-ups, I would also include Dubravka (7.3) to the watchlist. Newcastle's form and numbers are pretty high if we exclude their loss against Man City (we can't really perceive this result as valuable, remembering the opponent's level).

Best Budget Option

Butland (or Guaita) is my best budget option. We know how strong Crystal Palace could be on home turf. Man Utd are obviously struggling (they have lost 0-4 against Brighton in their last away match) so 6.7 for The Eagles' goalkeeper looks like a good deal.

Everton's morale has to be much higher than Arsenal because they have achieved their most important goal and remained in the league. Arsenal have just theoretical chances to qualify to UEFA Champions League next season (Tottenham have to lose their match against Norwich). It's doubtful that Everton are able to keep a clean sheet, but we don't have to pay a lot for Pickford. I don't think Arsenal will score a lot of goals and paying 6.1 for Pickford we can get a good value if he makes some saves.

 

Montafly
Author

Montafly

Matvey, also known as Montafly is a big fantasy fan, Excel master and music lover who likes making useful spreadsheets and digging up interesting statistics for fantasy games. He has been playing DFS since 2019 on FanTeam and for 10 years on FPL. FanTeam's 2019 Winter Championship of Fantasy Football finalist. FanTeam's 2021 Spring Championship of Fantasy Football finalist and prize-winner. 38th in FanTeam EURO 2020 £1M Game

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