FairValue

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Wouter

Prins

LBNetherlands · FC Groningen

№ 671734Emerging €638k −0.35

Player dossierEredivisie

WouterPrins

LBLeft-BackDefender

Club
FC Groningen
League
Eredivisie
Nationality
Netherlands
Age
22
Height
173 cm
Foot
Left
Valued
28 May 2026

Reading the valuation

The market values Prins at €450k. Model A, which never saw Prins during training, estimates €638k: the market value is 29% below that estimate.

That is a factor of ×1.42. 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 €998k, 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.

▼ −0.35A €638k▼ −0.80B €998k
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
49
Minutes
2,231
Goals
1
Assists
3
Started
24/49
Min / app
46
Cards
2Y 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 Prins…

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 €450k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €450kModel A €638k

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 Prins's percentiles among defenders: Goals per 90 57th, Assists per 90 82nd, Minutes, two years 38th, Starts 7th, Minutes, last 365 days 11th, European club minutes 30th57thGoals82ndAssists38thMinutes7thStarts11thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.12 this player0.04 defender median82nd percentile

0.00peer deciles · median line · this player ●0.58

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
€200k
Jan 2024
Peak
€800k
Mar 2025
Model target
€450k
May 2026
Valuations
8
0 club changes
May 2026€450kFC GroningenValuation the model is trained to reproduce

May 2026: €450k, FC Groningen. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2024-01-08€200kFC Groningen
2024-06-10€325kFC Groningen
2024-10-14€500kFC Groningen
2024-12-17€600kFC Groningen
2025-03-28€800kFC Groningen
2025-05-28€800kFC Groningen
2025-12-02€600kFC Groningen
2026-05-28€450kFC Groningen

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
−0.349

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 22% of the 425 Eredivisie players.

€75k€500k€3M€20M€450kSee them in the Explorer →

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

Valued above 17% of the 2,065 defenders.

€20k€200k€2M€20M€450kSee them in the Explorer →

Where Prins 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).