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Portrait of James Tarkowski

James

Tarkowski

CBEngland · Everton FC

№ 173504Established €5.5M −0.10

Image: FootyLogos

Player dossierPremier League

JamesTarkowski

CBCentre-BackDefender

Club
Everton FC
League
Premier League
Nationality
England
Age
33
Height
185 cm
Foot
Right
Valued
3 Jun 2026

Reading the valuation

The market values Tarkowski at €5M. Model A, which never saw Tarkowski during training, estimates €5.5M: the market value is 9% below that estimate.

That is a factor of ×1.10. 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 €2.4M, 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.

▼ −0.10A €5.5M▲ +0.75B €2.4M
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
74
Minutes
6,644
Goals
3
Assists
4
Started
74/74
Min / app
90
Cards
14Y 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 Tarkowski…

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 €5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €5MModel A €5.5M

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 2,065 defenders

James Tarkowski's percentiles among defenders: Goals per 90 57th, Assists per 90 59th, Minutes, two years 96th, Starts 97th, Minutes, last 365 days 97th, European club minutes 30th57thGoals59thAssists96thMinutes97thStarts97thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Starts

Share of appearances started rather than entered from the bench.

100% this player83% defender median97th percentile

18%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
€50k
Feb 2011
Peak
€28M
Oct 2020
Model target
€5M
Jun 2026
Valuations
28
3 club changes
Jun 2026€5MEverton FCValuation the model is trained to reproduce

Jun 2026: €5M, Everton FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2011-02-03€50kOldham Athletic
2014-03-28€200kBrentford FC
2015-02-24€350kBrentford FC
2015-09-24€350kBrentford FC
2016-04-20€2MBurnley FC
2016-08-01€2MBurnley FC
2017-02-20€2MBurnley FC
2017-06-28€2MBurnley FC
2017-10-23€3MBurnley FC
2018-01-02€6MBurnley FC
2018-05-28€15MBurnley FC
2018-12-19€15MBurnley FC
2019-06-13€18MBurnley FC
2019-12-10€25MBurnley FC
2020-04-08€20MBurnley FC
2020-10-13€28MBurnley FC
2021-03-18€25MBurnley FC
2021-06-08€25MBurnley FC
2021-12-23€22MBurnley FC
2022-06-15€22MBurnley FC
2022-11-03€22MEverton FC
2023-06-20€18MEverton FC
2023-12-19€13MEverton FC
2024-05-27€13MEverton FC
2024-12-16€10MEverton FC
2025-05-30€9MEverton FC
2025-12-09€7MEverton FC
2026-06-03€5MEverton FC

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
−0.100

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 21% of the 555 Premier League players.

€150k€1M€7.5M€50M€5MSee them in the Explorer →

Defenders, all leagues2,065 players · median €2M

Valued above 70% of the 2,065 defenders.

€20k€200k€2M€20M€5MSee them in the Explorer →

Where Tarkowski 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).