FairValue

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Portrait of Sam Johnstone

Sam

Johnstone

GKEngland · Wolverhampton Wanderers

№ 110864Established €1.6M +0.24

Image: FootyLogos

Player dossierPremier League

SamJohnstone

GKGoalkeeperGoalkeeper

Club
Wolverhampton Wanderers
League
Premier League
Nationality
England
Age
33
Height
193 cm
Foot
Right
Valued
3 Jun 2026

Reading the valuation

The market values Johnstone at €2M. Model A, which never saw Johnstone during training, estimates €1.6M: the market value is 27% above that estimate.

That is a factor of ×1.27. Model A's typical held-out miss is ×1.50 either way, so this gap is within its usual error.

Without league and club, Model B estimates €332k, further from the market. Model B is usually further off (typical miss ×2.07): league and club explain much of how the market prices players.

A gap describes the model's arithmetic for this player's inputs, not what the player is worth.

▲ +0.24A €1.6M▲ +1.80B €332k
Pitch length is a log value scale fitted to this player's figures. ● observed · ◇ Model A · dashed ◇ Model B · each arc is a residual, log(observed) − log(estimate).
Apps
27
Minutes
2,460
Started
27/27
Min / app
91
Cards
0Y 0R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Johnstone…

SHAP describes the model's arithmetic for this player's inputs, not what causes market value. Model B can be explained only by the live service; Model A also has a published explanation for the research players.

Model A vs Model B against the observed €2M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €2MModel A €1.6M

Asking the prediction API…

Held-out estimates come from cross-validation, with this player outside the training data: the honest comparison. Served models were refitted on every player, this one included, so they sit closer to the market. Shaded band: Model A's typical miss (×1.50 either way).

Player traitspercentiles vs 485 goalkeepers

Sam Johnstone's percentiles among goalkeepers: Minutes, two years 45th, Starts 62nd, Minutes, last 365 days 49th, European club minutes 32nd45thMinutes62ndStarts49thRecent32ndEurope

Dashed ring: the goalkeeper median (50th percentile)

Starts

Share of appearances started rather than entered from the bench.

100% this player100% goalkeeper median62nd percentile

70%peer deciles · median line · this player ●100%

No passing, progression or defensive actions exist in the dataset, so no trait claims to measure them.

Valuation history every Transfermarkt valuation on record

First valuation
€250k
Jul 2013
Peak
€12M
May 2022
Model target
€2M
Jun 2026
Valuations
29
8 club changes
Jun 2026€2MWolverhampton WanderersValuation the model is trained to reproduce

Jun 2026: €2M, Wolverhampton Wanderers. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2013-07-25€250kManchester United
2015-02-27€250kPreston North End
2015-07-01€250kManchester United
2016-02-09€250kManchester United
2016-08-01€250kManchester United
2017-02-27€500kAston Villa
2017-06-28€1MManchester United
2018-02-27€2.5MAston Villa
2018-09-24€7MWest Bromwich Albion
2019-06-28€7MWest Bromwich Albion
2020-02-27€7MWest Bromwich Albion
2020-04-08€5.5MWest Bromwich Albion
2020-10-13€6.5MWest Bromwich Albion
2021-03-18€6MWest Bromwich Albion
2021-05-28€8MWest Bromwich Albion
2021-11-24€8MWest Bromwich Albion
2022-05-13€12MWest Bromwich Albion
2022-09-15€8MCrystal Palace
2022-11-03€6MCrystal Palace
2023-03-16€4MCrystal Palace
2023-06-20€6MCrystal Palace
2023-10-09€10MCrystal Palace
2023-12-19€12MCrystal Palace
2024-05-27€10MCrystal Palace
2024-12-16€8MWolverhampton Wanderers
2025-05-30€6MWolverhampton Wanderers
2025-12-09€5MWolverhampton Wanderers
2026-03-09€3MWolverhampton Wanderers
2026-06-03€2MWolverhampton Wanderers

Audit context group-level, not about this player

Audit group
UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
+0.240

The group comes from first-listed citizenship and is never a model input. Across the population, non-UEFA players' market values sit about 10% above Model A's held-out estimates, relative to UEFA players in the same leagues. One player's residual says nothing about that pattern (typical miss ×1.50), and none of it is evidence of discrimination: the target may itself be biased. Open the Fairness Audit

In context observed value among comparable players in this build

All players in the Terminal →

Premier League555 players · median €18M

Valued above 9% of the 555 Premier League players.

€150k€1M€7.5M€50M€2MSee them in the Explorer →

Goalkeepers, all leagues485 players · median €1M

Valued above 59% of the 485 goalkeepers.

€20k€200k€2M€20M€2MSee them in the Explorer →

Where Johnstone appears

Watchlists and the comparison tray are kept in this browser only.

Near this valuation closest observed values: same league, then same position

Counts and ranks of observed Transfermarkt values only; model errors are never ranked here. Full player export: Every player in the modelling population (D-011).