FairValue

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Portrait of Owen Wijndal

Owen

Wijndal

LBNetherlands · Ajax Amsterdam

№ 339328Established €2.1M +0.34

Close-up

Image: FootyLogos

Player dossierEredivisie

OwenWijndal

LBLeft-BackDefender

Club
Ajax Amsterdam
League
Eredivisie
Nationality
Netherlands
Age
26
Height
176 cm
Foot
Left
Valued
28 May 2026

Reading the valuation

The market values Wijndal at €3M. Model A, which never saw Wijndal during training, estimates €2.1M: the market value is 40% above that estimate.

That is a factor of ×1.40. 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 €2.6M, 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.

▲ +0.34A €2.1M▲ +0.15B €2.6M
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
40
Minutes
2,353
Goals
2
Assists
1
Started
26/40
Min / app
59
Cards
8Y 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 Wijndal…

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 €3M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €3MModel A €2.1M

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

Owen Wijndal's percentiles among defenders: Goals per 90 79th, Assists per 90 49th, Minutes, two years 41st, Starts 21st, Minutes, last 365 days 58th, European club minutes 87th79thGoals49thAssists41stMinutes21stStarts58thRecent87thEurope

Dashed ring: the defender median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

22% this player0% defender median87th percentile

0%peer deciles · median line · this player ●85%

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
€100k
Feb 2017
Peak
€17.5M
May 2021
Model target
€3M
May 2026
Valuations
28
4 club changes
May 2026€3MAjax AmsterdamValuation the model is trained to reproduce

May 2026: €3M, Ajax Amsterdam. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2017-02-04€100kAZ Alkmaar U21
2017-06-07€150kAZ Alkmaar U21
2018-01-17€500kAZ Alkmaar
2018-06-12€750kAZ Alkmaar
2018-12-28€750kAZ Alkmaar
2019-06-12€1MAZ Alkmaar
2019-09-19€3MAZ Alkmaar
2019-12-18€9MAZ Alkmaar
2020-03-12€12MAZ Alkmaar
2020-04-08€11MAZ Alkmaar
2020-10-14€11MAZ Alkmaar
2021-01-06€15MAZ Alkmaar
2021-05-27€17.5MAZ Alkmaar
2021-10-04€15MAZ Alkmaar
2022-01-05€12MAZ Alkmaar
2022-06-08€12MAZ Alkmaar
2022-11-11€12MAjax Amsterdam
2023-03-17€10MAjax Amsterdam
2023-06-23€8MAjax Amsterdam
2023-10-23€7MRoyal Antwerp FC
2023-12-19€5.5MRoyal Antwerp FC
2024-06-04€5.5MRoyal Antwerp FC
2024-10-14€4.5MAjax Amsterdam
2024-12-17€4MAjax Amsterdam
2025-05-28€3.5MAjax Amsterdam
2025-10-02€4.5MAjax Amsterdam
2025-12-02€4MAjax Amsterdam
2026-05-28€3MAjax Amsterdam

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
+0.337

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 70% of the 425 Eredivisie players.

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

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

Valued above 59% of the 2,065 defenders.

€20k€200k€2M€20M€3MSee them in the Explorer →

Where Wijndal 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).