Bart
Nieuwkoop
RBNetherlands · Feyenoord Rotterdam
Player dossierEredivisie
BartNieuwkoop
RBRight-BackDefender
- Club
- Feyenoord Rotterdam
- League
- Eredivisie
- Nationality
- Netherlands
- Age
- 30
- Height
- 181 cm
- Foot
- Right
- Valued
- 28 May 2026
Reading the valuation
The market values Nieuwkoop at €1.5M. Model A, which never saw Nieuwkoop during training, estimates €1.2M: the market value is 30% above that estimate.
That is a factor of ×1.30. 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 €1.2M, 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
- 39
- Minutes
- 1,597
- Goals
- 2
- Assists
- 2
- Started
- 18/39
- Min / app
- 41
- Cards
- 6Y 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 Nieuwkoop…
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)
European club minutes
Share of minutes played in UEFA club competitions.
33% this player0% defender median96th 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
- €50k
- Jul 2015
- Peak
- €4M
- Dec 2023
- Model target
- €1.5M
- May 2026
- Valuations
- 25
- 4 club changes
May 2026: €1.5M, Feyenoord Rotterdam. Dotted lines mark the €2M, €10M and €30M tier boundaries.
Show as a table
| Date | Market value | Club |
|---|---|---|
| 2015-07-01 | €50k | Feyenoord Rotterdam |
| 2015-11-11 | €350k | Feyenoord Rotterdam |
| 2016-02-05 | €500k | Feyenoord Rotterdam |
| 2016-07-15 | €750k | Feyenoord Rotterdam |
| 2017-01-18 | €750k | Feyenoord Rotterdam |
| 2017-06-07 | €1.5M | Feyenoord Rotterdam |
| 2018-01-17 | €1.5M | Feyenoord Rotterdam |
| 2018-06-12 | €1.3M | Feyenoord Rotterdam |
| 2018-12-28 | €1.5M | Feyenoord Rotterdam |
| 2019-06-12 | €1.5M | Feyenoord Rotterdam |
| 2019-12-18 | €1.5M | Willem II Tilburg |
| 2020-04-08 | €1.2M | Willem II Tilburg |
| 2020-10-14 | €2M | Feyenoord Rotterdam |
| 2021-01-06 | €2.5M | Feyenoord Rotterdam |
| 2021-05-19 | €2.2M | Feyenoord Rotterdam |
| 2022-01-06 | €2.2M | Union Saint-Gilloise |
| 2022-04-12 | €2.5M | Union Saint-Gilloise |
| 2022-11-04 | €2.5M | Union Saint-Gilloise |
| 2023-06-09 | €3M | Union Saint-Gilloise |
| 2023-12-15 | €4M | Feyenoord Rotterdam |
| 2024-05-31 | €4M | Feyenoord Rotterdam |
| 2024-12-17 | €3M | Feyenoord Rotterdam |
| 2025-05-28 | €2M | Feyenoord Rotterdam |
| 2025-12-02 | €2M | Feyenoord Rotterdam |
| 2026-05-28 | €1.5M | Feyenoord 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
- +0.265
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 Nieuwkoop 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
- SampstedRBGo Ahead Eagles · Eredivisie€1.5M
- SchendelaarGKPEC Zwolle · 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).