FairValue

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Wouter

Goes

CBNetherlands · AZ Alkmaar

№ 646707Elite €10.1M +0.39

Player dossierEredivisie

WouterGoes

CBCentre-BackDefender

Club
AZ Alkmaar
League
Eredivisie
Nationality
Netherlands
Age
21
Height
188 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Goes at €15M. Model A, which never saw Goes during training, estimates €10.1M: the market value is 48% above that estimate.

That is a factor of ×1.48. 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 €27.8M, 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.

▲ +0.39A €10.1M▼ −0.62B €27.8M
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
83
Minutes
6,921
Goals
3
Assists
3
Started
78/83
Min / app
83
Cards
25Y 1R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Goes…

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 €10.1M

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

Wouter Goes's percentiles among defenders: Goals per 90 56th, Assists per 90 50th, Minutes, two years 98th, Starts 81st, Minutes, last 365 days 97th, European club minutes 82nd56thGoals50thAssists98thMinutes81stStarts97thRecent82ndEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

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

6,921 this player2,860 defender median98th 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
€25k
Mar 2022
Peak
€15M
Mar 2026
Model target
€15M
May 2026
Valuations
13
1 club change
May 2026€15MAZ AlkmaarValuation the model is trained to reproduce

May 2026: €15M, AZ Alkmaar. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2022-03-24€25kAZ Alkmaar U21
2022-06-23€100kAZ Alkmaar U21
2023-03-17€1.3MAZ Alkmaar U21
2023-06-23€2MAZ Alkmaar U21
2023-12-15€2MAZ Alkmaar
2024-03-18€4.5MAZ Alkmaar
2024-05-31€5MAZ Alkmaar
2024-12-17€5MAZ Alkmaar
2025-03-28€8MAZ Alkmaar
2025-05-28€10MAZ Alkmaar
2025-12-02€12MAZ Alkmaar
2026-03-11€15MAZ Alkmaar
2026-05-28€15MAZ Alkmaar

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
+0.391

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 →

Eredivisie425 players · median €1M

Valued above 95% of the 425 Eredivisie players.

€75k€500k€3M€20M€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 Goes 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).