FairValue

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Calvin

Verdonk

LBIndonesia · LOSC Lille

№ 258364Established €9.2M −1.30

Player dossierLigue 1

CalvinVerdonk

LBLeft-BackDefender

Club
LOSC Lille
League
Ligue 1
Nationality
Indonesia
Age
29
Height
174 cm
Foot
Left
Valued
1 Jun 2026

Reading the valuation

The market values Verdonk at €2.5M. Model A, which never saw Verdonk during training, estimates €9.2M: the market value is 73% below that estimate.

That is a factor of ×3.67. 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 €5.5M, 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.

▼ −1.30A €9.2M▼ −0.79B €5.5M
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
64
Minutes
4,615
Goals
1
Assists
3
Started
48/64
Min / app
72
Cards
13Y 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 Verdonk…

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 €2.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €2.5MModel A €9.2M

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

Calvin Verdonk's percentiles among defenders: Goals per 90 40th, Assists per 90 62nd, Minutes, two years 78th, Starts 35th, Minutes, last 365 days 47th, European club minutes 71st40thGoals62ndAssists78thMinutes35thStarts47thRecent71stEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

Total club minutes in the two-year window: how much the player was used.

4,615 this player2,860 defender median78th percentile

451peer deciles · median line · this player ●9,111

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
Mar 2015
Peak
€3M
Oct 2025
Model target
€2.5M
Jun 2026
Valuations
28
8 club changes
Jun 2026€2.5MLOSC LilleValuation the model is trained to reproduce

Jun 2026: €2.5M, LOSC Lille. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2015-03-08€50kFeyenoord/Excelsior U19
2015-07-01€150kFeyenoord Rotterdam
2016-02-05€150kFeyenoord Rotterdam
2016-07-15€250kPEC Zwolle
2017-01-18€650kPEC Zwolle
2017-06-07€550kPEC Zwolle
2018-03-01€450kNEC Nijmegen
2018-06-29€500kNEC Nijmegen
2018-12-28€1MFeyenoord Rotterdam
2019-03-13€2MFeyenoord Rotterdam
2019-06-12€2MFeyenoord Rotterdam
2019-12-18€2MFC Twente Enschede
2020-04-08€1.6MFC Twente Enschede
2020-10-22€1.6MFC Famalicão
2021-01-28€1.3MFC Famalicão
2021-05-21€900kFC Famalicão
2022-01-05€700kNEC Nijmegen
2022-06-08€700kNEC Nijmegen
2022-11-11€800kNEC Nijmegen
2023-06-23€800kNEC Nijmegen
2023-12-15€1.2MNEC Nijmegen
2024-03-18€1.8MNEC Nijmegen
2024-05-31€2.5MNEC Nijmegen
2024-12-17€2.5MNEC Nijmegen
2025-05-28€2.5MNEC Nijmegen
2025-10-10€3MLOSC Lille
2025-12-15€3MLOSC Lille
2026-06-01€2.5MLOSC Lille

Audit context group-level, not about this player

Audit group
non-UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
−1.300

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 →

Ligue 1423 players · median €5M

Valued above 24% of the 423 Ligue 1 players.

€100k€750k€5M€30M€2.5MSee them in the Explorer →

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

Valued above 54% of the 2,065 defenders.

€20k€200k€2M€20M€2.5MSee them in the Explorer →

Where Verdonk 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).