FairValue

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Portrait of Aaron Wan-Bissaka

Aaron

Wan-Bissaka

RBDR Congo · West Ham United

№ 477758Elite €12.8M +0.16

Image: FootyLogos

Player dossierPremier League

AaronWan-Bissaka

RBRight-BackDefender

Club
West Ham United
League
Premier League
Nationality
DR Congo
Age
28
Height
183 cm
Foot
Right
Valued
3 Jun 2026

Reading the valuation

The market values Wan-Bissaka at €15M. Model A, which never saw Wan-Bissaka during training, estimates €12.8M: the market value is 17% above that estimate.

That is a factor of ×1.17. 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 €3.8M, 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.

▲ +0.16A €12.8M▲ +1.39B €3.8M
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
65
Minutes
5,539
Goals
2
Assists
8
Started
61/65
Min / app
85
Cards
7Y 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 Wan-Bissaka…

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 €15M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €15MModel A €12.8M

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

Aaron Wan-Bissaka's percentiles among defenders: Goals per 90 51st, Assists per 90 84th, Minutes, two years 89th, Starts 81st, Minutes, last 365 days 68th, European club minutes 30th51stGoals84thAssists89thMinutes81stStarts68thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

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

5,539 this player2,860 defender median89th 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
€1M
May 2018
Peak
€40M
Sept 2019
Model target
€15M
Jun 2026
Valuations
25
2 club changes
Jun 2026€15MWest Ham UnitedValuation the model is trained to reproduce

Jun 2026: €15M, West Ham United. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2018-05-28€1MCrystal Palace
2018-10-17€5MCrystal Palace
2018-12-19€10MCrystal Palace
2019-03-05€25MCrystal Palace
2019-06-13€35MCrystal Palace
2019-09-12€40MManchester United
2019-12-10€40MManchester United
2020-04-08€32MManchester United
2020-07-30€40MManchester United
2020-10-13€40MManchester United
2021-03-18€40MManchester United
2021-06-08€40MManchester United
2021-12-23€38MManchester United
2022-03-29€30MManchester United
2022-06-15€25MManchester United
2022-09-15€18MManchester United
2022-11-03€18MManchester United
2023-03-16€22MManchester United
2023-06-20€25MManchester United
2023-12-19€20MManchester United
2024-05-27€20MManchester United
2024-12-16€22MWest Ham United
2025-05-30€24MWest Ham United
2025-12-09€22MWest Ham United
2026-06-03€15MWest Ham United

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
+0.159

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 43% of the 555 Premier League players.

€150k€1M€7.5M€50M€15MSee them in the Explorer →

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

Valued above 87% of the 2,065 defenders.

€20k€200k€2M€20M€15MSee them in the Explorer →

Where Wan-Bissaka 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).