Deveron
Fonville
CBCuracao · NEC Nijmegen
Player dossierEredivisie
DeveronFonville
CBCentre-BackDefender
- Club
- NEC Nijmegen
- League
- Eredivisie
- Nationality
- Curacao
- Age
- 23
- Height
- 188 cm
- Foot
- Left
- Valued
- 28 May 2026
EredivisieReading the valuation
The market values Fonville at €1.5M. Model A, which never saw Fonville during training, estimates €2.9M: the market value is 49% below that estimate.
That is a factor of ×1.95. 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 €2.1M, 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.
- Apps
- 34
- Minutes
- 1,710
- Goals
- 0
- Assists
- 3
- Started
- 16/34
- Min / app
- 50
- Cards
- 4Y 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 Fonville…
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 €1.5M
Checking APIAsking 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
Dashed ring: the defender median (50th percentile)
Assists per 90
Club assists per 90 minutes in the same window.
0.16 this player0.04 defender median90th percentile
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
- €450k
- Sept 2025
- Peak
- €1.5M
- May 2026
- Model target
- €1.5M
- May 2026
- Valuations
- 5
- 1 club change
May 2026: €1.5M, NEC Nijmegen. Dotted lines mark the €2M, €10M and €30M tier boundaries.
Show as a table
| Date | Market value | Club |
|---|---|---|
| 2025-09-01 | €450k | FC Dordrecht |
| 2025-10-02 | €850k | NEC Nijmegen |
| 2025-12-02 | €850k | NEC Nijmegen |
| 2026-03-11 | €1M | NEC Nijmegen |
| 2026-05-28 | €1.5M | NEC Nijmegen |
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
- −0.669
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 54% of the 425 Eredivisie players.
See them in the Explorer →Defenders, all leagues2,065 players · median €2M
Valued above 43% of the 2,065 defenders.
See them in the Explorer →Where Fonville appears
Watchlists and the comparison tray are kept in this browser only.
Near this valuation closest observed values: same league, then same position
- TraunerCBFeyenoord Rotterdam · Eredivisie€1.5M
- PjacaLWFC Twente Enschede · Eredivisie€1.5M
- NieuwkoopRBFeyenoord Rotterdam · Eredivisie€1.5M
- SampstedRBGo Ahead Eagles · Eredivisie€1.5M
- KüblerRBSC Freiburg · defenders€1.5M
- WalkerRBBurnley FC · defenders€1.5M
- TrippierRBNewcastle United · defenders€1.5M
- MeunierRBLOSC Lille · defenders€1.5M
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).