FairValue

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Tom de

Graaff

GKNetherlands · PEC Zwolle

№ 729010Emerging €1.6M −0.46

Player dossierEredivisie

Tom deGraaff

GKGoalkeeperGoalkeeper

Club
PEC Zwolle
League
Eredivisie
Nationality
Netherlands
Age
21
Height
193 cm
Foot
Left
Valued
28 May 2026

Reading the valuation

The market values Graaff at €1M. Model A, which never saw Graaff during training, estimates €1.6M: the market value is 37% below that estimate.

That is a factor of ×1.58. 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 €5.2M, 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.

▼ −0.46A €1.6M▼ −1.65B €5.2M
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
33
Minutes
2,970
Started
33/33
Min / app
90
Cards
0Y 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 Graaff…

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 €1M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1MModel A €1.6M

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 485 goalkeepers

Tom de Graaff's percentiles among goalkeepers: Minutes, two years 54th, Starts 62nd, Minutes, last 365 days 78th, European club minutes 32nd54thMinutes62ndStarts78thRecent32ndEurope

Dashed ring: the goalkeeper median (50th percentile)

Minutes, last 365 days

Club minutes in the final year of the window: recent involvement, or the absence of it.

2,970 this player1,560 goalkeeper median78th percentile

0peer deciles · median line · this player ●4,970

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
€250k
Oct 2022
Peak
€1M
May 2026
Model target
€1M
May 2026
Valuations
11
2 club changes
May 2026€1MPEC ZwolleValuation the model is trained to reproduce

May 2026: €1M, PEC Zwolle. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2022-10-12€250kAjax Amsterdam U21
2023-04-03€400kAjax Amsterdam U21
2023-07-04€400kAjax Amsterdam U21
2024-01-08€300kAjax Amsterdam U21
2024-06-10€400kAjax Amsterdam U21
2024-12-17€350kFC Utrecht
2025-05-28€300kFC Utrecht
2025-10-02€600kPEC Zwolle
2025-12-02€600kPEC Zwolle
2026-03-11€900kPEC Zwolle
2026-05-28€1MPEC Zwolle

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
−0.456

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 46% of the 425 Eredivisie players.

€75k€500k€3M€20M€1MSee them in the Explorer →

Goalkeepers, all leagues485 players · median €1M

Valued above 48% of the 485 goalkeepers.

€20k€200k€2M€20M€1MSee them in the Explorer →

Where Graaff 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).