FairValue

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Portrait of Calvin Bassey

Calvin

Bassey

CBNigeria · Fulham FC

№ 461883Elite €36.1M −0.25

Image: FootyLogos

Player dossierPremier League

CalvinBassey

CBCentre-BackDefender

Club
Fulham FC
League
Premier League
Nationality
Nigeria
Age
26
Height
185 cm
Foot
Left
Valued
3 Jun 2026

Reading the valuation

The market values Bassey at €28M. Model A, which never saw Bassey during training, estimates €36.1M: the market value is 22% below that estimate.

That is a factor of ×1.29. 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 €8M, 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.

▼ −0.25A €36.1M▲ +1.25B €8M
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
69
Minutes
5,932
Goals
3
Assists
1
Started
65/69
Min / app
86
Cards
12Y 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 Bassey…

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 €28M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €28MModel A €36.1M

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

Calvin Bassey's percentiles among defenders: Goals per 90 61st, Assists per 90 35th, Minutes, two years 92nd, Starts 82nd, Minutes, last 365 days 80th, European club minutes 30th61stGoals35thAssists92ndMinutes82ndStarts80thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

Total club minutes in the two-year window: how much the player was used.

5,932 this player2,860 defender median92nd percentile

451peer deciles · median line · this player ●9,111

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
€150k
Jul 2020
Peak
€28M
Oct 2025
Model target
€28M
Jun 2026
Valuations
16
2 club changes
Jun 2026€28MFulham FCValuation the model is trained to reproduce

Jun 2026: €28M, Fulham FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-07-21€150kRangers FC
2021-01-18€500kRangers FC
2021-06-28€400kRangers FC
2021-12-31€1MRangers FC
2022-06-27€10MRangers FC
2022-09-14€18MAjax Amsterdam
2022-11-11€18MAjax Amsterdam
2023-06-23€15MAjax Amsterdam
2023-12-19€16MFulham FC
2024-05-27€16MFulham FC
2024-12-16€16MFulham FC
2025-03-18€25MFulham FC
2025-05-30€25MFulham FC
2025-10-17€28MFulham FC
2025-12-09€28MFulham FC
2026-06-03€28MFulham FC

Audit context group-level, not about this player

Audit group
non-UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
−0.253

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 69% of the 555 Premier League players.

€150k€1M€7.5M€50M€28MSee them in the Explorer →

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

Valued above 95% of the 2,065 defenders.

€20k€200k€2M€20M€28MSee them in the Explorer →

Where Bassey 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).