Siebe Van der
Heyden
CBBelgium · KAA Gent
Player dossierPro League
Siebe Van derHeyden
CBCentre-BackDefender
- Club
- KAA Gent
- League
- Pro League
- Nationality
- Belgium
- Age
- 28
- Height
- 185 cm
- Foot
- Left
- Valued
- 4 Jun 2026
Reading the valuation
The market values Heyden at €3M. Model A, which never saw Heyden during training, estimates €2.6M: the market value is 17% above that estimate.
That is a factor of ×1.17. 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 €3.3M, 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
- 50
- Minutes
- 3,927
- Goals
- 3
- Assists
- 1
- Started
- 45/50
- Min / app
- 79
- Cards
- 14Y 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 Heyden…
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 €3M
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)
Minutes, last 365 days
Club minutes in the final year of the window: recent involvement, or the absence of it.
2,955 this player1,687 defender median88th 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
- €150k
- Jul 2016
- Peak
- €4M
- Jun 2023
- Model target
- €3M
- Jun 2026
- Valuations
- 23
- 5 club changes
Jun 2026: €3M, KAA Gent. Dotted lines mark the €2M, €10M and €30M tier boundaries.
Show as a table
| Date | Market value | Club |
|---|---|---|
| 2016-07-15 | €150k | KV Oostende (-2024) |
| 2017-01-21 | €150k | KV Oostende (-2024) |
| 2017-06-06 | €150k | KV Oostende (-2024) |
| 2018-01-09 | €100k | KV Oostende (-2024) |
| 2018-06-03 | €100k | KV Oostende (-2024) |
| 2019-01-21 | €275k | FC Eindhoven |
| 2019-07-03 | €275k | FC Eindhoven |
| 2019-11-13 | €300k | Union Saint-Gilloise |
| 2020-03-30 | €300k | Union Saint-Gilloise |
| 2020-10-21 | €300k | Union Saint-Gilloise |
| 2021-02-23 | €500k | Union Saint-Gilloise |
| 2021-10-06 | €700k | Union Saint-Gilloise |
| 2022-01-06 | €1M | Union Saint-Gilloise |
| 2022-04-12 | €3M | Union Saint-Gilloise |
| 2022-11-04 | €3M | Union Saint-Gilloise |
| 2023-06-09 | €4M | Union Saint-Gilloise |
| 2023-12-22 | €3M | RCD Mallorca |
| 2024-06-07 | €2M | RCD Mallorca |
| 2024-12-27 | €1.5M | RCD Mallorca |
| 2025-03-27 | €2M | FC St. Pauli |
| 2025-06-05 | €2.5M | FC St. Pauli |
| 2025-12-10 | €3M | KAA Gent |
| 2026-06-04 | €3M | KAA Gent |
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
- +0.160
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 →Pro League350 players · median €1.8M
Valued above 67% of the 350 Pro League players.
See them in the Explorer →Defenders, all leagues2,065 players · median €2M
Valued above 59% of the 2,065 defenders.
See them in the Explorer →Where Heyden appears
Watchlists and the comparison tray are kept in this browser only.
Near this valuation closest observed values: same league, then same position
- KerkRWRoyal Antwerp FC · Pro League€3M
- ItoRWKRC Genk · Pro League€3M
- KangaCFKAA Gent · Pro League€3M
- KanaCBRSC Anderlecht · Pro League€3M
- AlabaCBReal Madrid · defenders€3M
- VrijCBInter Milan · defenders€3M
- KeaneCBEverton FC · defenders€3M
- WeiserRBSV Werder Bremen · defenders€3M
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).