Jan
Zamburek
CMCzech Republic · Heracles Almelo
Player dossierEredivisie
JanZamburek
CMCentral MidfieldMidfield
- Club
- Heracles Almelo
- League
- Eredivisie
- Nationality
- Czech Republic
- Age
- 25
- Height
- 182 cm
- Foot
- Left
- Valued
- 28 May 2026
EredivisieReading the valuation
The market values Zamburek at €400k. Model A, which never saw Zamburek during training, estimates €502k: the market value is 20% below that estimate.
That is a factor of ×1.26. 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 €1.9M, 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.
- Apps
- 53
- Minutes
- 3,251
- Goals
- 0
- Assists
- 3
- Started
- 38/53
- Min / app
- 61
- Cards
- 10Y 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 Zamburek…
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 €400k
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 1,687 midfielders
Dashed ring: the midfielder median (50th percentile)
Minutes, last 365 days
Club minutes in the final year of the window: recent involvement, or the absence of it.
2,002 this player1,541 midfielder median65th 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
- Dec 2017
- Peak
- €900k
- Feb 2020
- Model target
- €400k
- May 2026
- Valuations
- 16
- 4 club changes
May 2026: €400k, Heracles Almelo. Dotted lines mark the €2M, €10M and €30M tier boundaries.
Show as a table
| Date | Market value | Club |
|---|---|---|
| 2017-12-19 | €50k | SK Slavia Prague U19 |
| 2019-10-17 | €150k | Brentford FC |
| 2020-02-27 | €900k | Brentford FC |
| 2020-04-08 | €800k | Brentford FC |
| 2021-03-10 | €800k | Brentford FC |
| 2021-06-30 | €800k | Brentford FC |
| 2021-12-23 | €800k | Brentford FC |
| 2022-06-20 | €500k | Viborg FF |
| 2022-12-22 | €500k | Viborg FF |
| 2023-06-26 | €500k | Viborg FF |
| 2023-12-20 | €550k | FC Slovan Liberec |
| 2024-06-05 | €600k | FC Slovan Liberec |
| 2024-12-17 | €600k | Heracles Almelo |
| 2025-05-28 | €450k | Heracles Almelo |
| 2025-12-02 | €500k | Heracles Almelo |
| 2026-05-28 | €400k | Heracles Almelo |
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
- −0.227
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 18% of the 425 Eredivisie players.
See them in the Explorer →Midfielders, all leagues1,687 players · median €2M
Valued above 12% of the 1,687 midfielders.
See them in the Explorer →Where Zamburek appears
Watchlists and the comparison tray are kept in this browser only.
Near this valuation closest observed values: same league, then same position
- CheryAMNEC Nijmegen · Eredivisie€400k
- MisidjanLMNEC Nijmegen · Eredivisie€400k
- HalilovicAMFortuna Sittard · Eredivisie€400k
- LeemansCMNAC Breda · Eredivisie€400k
- WassCMBröndby IF · midfielders€400k
- BrasanacCMMálaga CF · midfielders€400k
- BruggenDMCercle Brugge · midfielders€400k
- KalinskiyDMFC Pari Nizhniy Novgorod · midfielders€400k
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).