FairValue

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Mees de

Wit

LBNetherlands · AZ Alkmaar

№ 315254Established €5.1M +0.16

Player dossierEredivisie

Mees deWit

LBLeft-BackDefender

Club
AZ Alkmaar
League
Eredivisie
Nationality
Netherlands
Age
28
Height
181 cm
Foot
Left
Valued
28 May 2026

Reading the valuation

The market values Wit at €6M. Model A, which never saw Wit during training, estimates €5.1M: 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 €11.3M, 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 €5.1M▼ −0.64B €11.3M
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
61
Minutes
4,131
Goals
6
Assists
13
Started
47/61
Min / app
68
Cards
15Y 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 Wit…

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 €6M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €6MModel A €5.1M

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

Mees de Wit's percentiles among defenders: Goals per 90 93rd, Assists per 90 99th, Minutes, two years 71st, Starts 39th, Minutes, last 365 days 95th, European club minutes 79th93rdGoals99thAssists71stMinutes39thStarts95thRecent79thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.28 this player0.04 defender median99th 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
Jun 2017
Peak
€6M
May 2026
Model target
€6M
May 2026
Valuations
17
4 club changes
May 2026€6MAZ AlkmaarValuation the model is trained to reproduce

May 2026: €6M, AZ Alkmaar. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2017-06-21€50kAjax Amsterdam U19
2018-03-01€75kAjax Amsterdam U21
2018-06-29€75kAjax Amsterdam U21
2020-02-11€50kOrihuela CF
2021-10-04€300kPEC Zwolle
2022-01-05€550kPEC Zwolle
2022-06-08€1.5MPEC Zwolle
2022-11-11€1.5MAZ Alkmaar
2023-06-23€1.5MAZ Alkmaar
2023-12-15€1.5MAZ Alkmaar
2024-05-31€2.5MAZ Alkmaar
2024-12-17€2.3MAZ Alkmaar
2025-05-28€1.5MAZ Alkmaar
2025-10-02€3MAZ Alkmaar
2025-12-02€3MAZ Alkmaar
2026-03-11€4.5MAZ Alkmaar
2026-05-28€6MAZ 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
+0.156

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 84% of the 425 Eredivisie players.

€75k€500k€3M€20M€6MSee them in the Explorer →

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

Valued above 73% of the 2,065 defenders.

€20k€200k€2M€20M€6MSee them in the Explorer →

Where Wit 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).