FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Milan

Zonneveld

CFNetherlands · Sparta Rotterdam

№ 818445Emerging €1.4M −1.14

Player dossierEredivisie

MilanZonneveld

CFCentre-ForwardAttack

Club
Sparta Rotterdam
League
Eredivisie
Nationality
Netherlands
Age
22
Height
198 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Zonneveld at €450k. Model A, which never saw Zonneveld during training, estimates €1.4M: the market value is 68% below that estimate.

That is a factor of ×3.11. 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 €3.4M, 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.

▼ −1.14A €1.4M▼ −2.03B €3.4M
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
34
Minutes
1,319
Goals
11
Assists
4
Started
12/34
Min / app
39
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 Zonneveld…

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 €1.4M

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 1,583 attackers

Milan Zonneveld's percentiles among attackers: Goals per 90 98th, Assists per 90 87th, Minutes, two years 27th, Starts 15th, Minutes, last 365 days 51st, European club minutes 28th98thGoals87thAssists27thMinutes15thStarts51stRecent28thEurope

Dashed ring: the attacker median (50th percentile)

Goals per 90

Club goals per 90 minutes played in the two years to the valuation date.

0.75 this player0.26 attacker median98th percentile

0.00peer deciles · median line · this player ●1.17

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
€450k
May 2026
Model target
€450k
May 2026
Valuations
5
2 club changes
May 2026€450kSparta RotterdamValuation the model is trained to reproduce

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

Show as a table
DateMarket valueClub
2022-03-24€25kFC Volendam U21
2022-06-23€25kFC Volendam U21
2025-09-20€300kSC Telstar
2025-12-02€300kSC Telstar
2026-05-28€450kSparta Rotterdam

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
−1.136

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 →

Attackers, all leagues1,583 players · median €2.5M

Valued above 14% of the 1,583 attackers.

€20k€300k€5M€75M€450kSee them in the Explorer →

Where Zonneveld 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).