FairValue

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Thomas

Ouwejan

CBNetherlands · NEC Nijmegen

№ 241477Emerging €1.1M −0.47

Player dossierEredivisie

ThomasOuwejan

CBCentre-BackDefender

Club
NEC Nijmegen
League
Eredivisie
Nationality
Netherlands
Age
29
Height
183 cm
Foot
Left
Valued
28 May 2026

Reading the valuation

The market values Ouwejan at €700k. Model A, which never saw Ouwejan during training, estimates €1.1M: the market value is 37% below that estimate.

That is a factor of ×1.59. Model A's typical held-out miss is ×1.50 either way, so this gap is larger than its usual error.

Without league and club, Model B estimates €905k, closer to the market here, although it is usually further off (typical miss ×2.07).

A gap describes the model's arithmetic for this player's inputs, not what the player is worth.

▼ −0.47A €1.1M▼ −0.26B €905k
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
39
Minutes
2,457
Goals
3
Assists
7
Started
28/39
Min / app
63
Cards
1Y 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 Ouwejan…

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 €700k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €700kModel A €1.1M

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

Thomas Ouwejan's percentiles among defenders: Goals per 90 90th, Assists per 90 98th, Minutes, two years 43rd, Starts 30th, Minutes, last 365 days 15th, European club minutes 30th90thGoals98thAssists43rdMinutes30thStarts15thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.26 this player0.04 defender median98th 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
€50k
Dec 2015
Peak
€3M
Dec 2018
Model target
€700k
May 2026
Valuations
27
3 club changes
May 2026€700kNEC NijmegenValuation the model is trained to reproduce

May 2026: €700k, NEC Nijmegen. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2015-12-10€50kAZ Alkmaar
2016-02-05€150kAZ Alkmaar
2016-07-15€250kAZ Alkmaar
2017-01-18€400kAZ Alkmaar
2017-06-07€400kAZ Alkmaar
2017-10-26€750kAZ Alkmaar
2018-01-17€1.5MAZ Alkmaar
2018-06-12€2.5MAZ Alkmaar
2018-12-28€3MAZ Alkmaar
2019-06-12€3MAZ Alkmaar
2019-12-18€3MAZ Alkmaar
2020-04-08€2.4MAZ Alkmaar
2020-10-29€2.5MUdinese Calcio
2020-12-29€2.5MUdinese Calcio
2021-06-03€2MUdinese Calcio
2021-12-15€2.5MFC Schalke 04
2022-06-16€2.5MFC Schalke 04
2022-11-09€2.5MFC Schalke 04
2023-06-22€2MFC Schalke 04
2023-12-15€1.7MFC Schalke 04
2024-03-22€1.5MFC Schalke 04
2024-06-06€1.5MFC Schalke 04
2024-12-17€1.2MNEC Nijmegen
2025-05-28€1.2MNEC Nijmegen
2025-10-02€800kNEC Nijmegen
2025-12-02€900kNEC Nijmegen
2026-05-28€700kNEC Nijmegen

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
−0.466

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 34% of the 425 Eredivisie players.

€75k€500k€3M€20M€700kSee them in the Explorer →

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

Valued above 26% of the 2,065 defenders.

€20k€200k€2M€20M€700kSee them in the Explorer →

Where Ouwejan 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).