Stefan
Velkov
CBBulgaria · Vejle Boldklub
Player dossierSuperliga
StefanVelkov
CBCentre-BackDefender
- Club
- Vejle Boldklub
- League
- Superliga
- Nationality
- Bulgaria
- Age
- 29
- Height
- 192 cm
- Foot
- Right
- Valued
- 25 May 2026
SuperligaReading the valuation
The market values Velkov at €650k. Model A, which never saw Velkov during training, estimates €734k: the market value is 11% below that estimate.
That is a factor of ×1.13. 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 €1.4M, 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
- 36
- Minutes
- 3,131
- Goals
- 5
- Assists
- 0
- Started
- 35/36
- Min / app
- 87
- 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 Velkov…
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 €650k
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)
Goals per 90
Club goals per 90 minutes played in the two years to the valuation date.
0.14 this player0.03 defender median95th 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
- €100k
- Aug 2013
- Peak
- €700k
- Dec 2025
- Model target
- €650k
- May 2026
- Valuations
- 28
- 5 club changes
May 2026: €650k, Vejle Boldklub. Dotted lines mark the €2M, €10M and €30M tier boundaries.
Show as a table
| Date | Market value | Club |
|---|---|---|
| 2013-08-07 | €100k | Slavia Sofia |
| 2013-10-21 | €200k | Slavia Sofia |
| 2014-03-10 | €300k | Slavia Sofia |
| 2015-07-28 | €300k | Slavia Sofia |
| 2015-12-17 | €300k | Slavia Sofia |
| 2016-08-07 | €300k | Slavia Sofia |
| 2017-01-28 | €300k | Slavia Sofia |
| 2017-08-23 | €300k | Slavia Sofia |
| 2018-02-09 | €300k | Slavia Sofia |
| 2018-08-10 | €350k | FC Den Bosch |
| 2019-01-21 | €400k | FC Den Bosch |
| 2019-07-03 | €400k | FC Den Bosch |
| 2020-03-12 | €400k | RKC Waalwijk |
| 2020-04-08 | €325k | RKC Waalwijk |
| 2020-11-11 | €300k | KFC Uerdingen 05 |
| 2021-01-20 | €250k | KFC Uerdingen 05 |
| 2021-06-14 | €250k | MSV Duisburg |
| 2021-12-30 | €225k | MSV Duisburg |
| 2022-06-01 | €200k | MSV Duisburg |
| 2022-09-13 | €250k | Vejle Boldklub |
| 2022-12-22 | €300k | Vejle Boldklub |
| 2023-06-26 | €350k | Vejle Boldklub |
| 2023-12-21 | €350k | Vejle Boldklub |
| 2024-06-10 | €500k | Vejle Boldklub |
| 2024-12-09 | €500k | Vejle Boldklub |
| 2025-06-16 | €600k | Vejle Boldklub |
| 2025-12-15 | €700k | Vejle Boldklub |
| 2026-05-25 | €650k | Vejle Boldklub |
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
- −0.122
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 →Superliga256 players · median €800k
Valued above 37% of the 256 Superliga players.
See them in the Explorer →Defenders, all leagues2,065 players · median €2M
Valued above 25% of the 2,065 defenders.
See them in the Explorer →Where Velkov appears
Watchlists and the comparison tray are kept in this browser only.
Near this valuation closest observed values: same league, then same position
- LissensCBRanders FC · Superliga€650k
- GabrielRBFC Midtjylland · Superliga€650k
- BachLWVejle Boldklub · Superliga€650k
- SimmelhackCFSilkeborg IF · Superliga€650k
- BehounekCBWillem II Tilburg · defenders€650k
- CappelleLBZulte Waregem · defenders€650k
- DekkerCBAZ Alkmaar · defenders€650k
- AertssenRBPEC Zwolle · defenders€650k
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).