FairValue

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Hristiyan

Petrov

CBBulgaria · SC Heerenveen

№ 628042Emerging €631k −0.23

Player dossierEredivisie

HristiyanPetrov

CBCentre-BackDefender

Club
SC Heerenveen
League
Eredivisie
Nationality
Bulgaria
Age
23
Height
186 cm
Foot
Left
Valued
28 May 2026

Reading the valuation

The market values Petrov at €500k. Model A, which never saw Petrov during training, estimates €631k: the market value is 21% 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 €823k, 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.

▼ −0.23A €631k▼ −0.50B €823k
Pitch length is a log value scale fitted to this player's figures. ● observed · ◇ Model A · dashed ◇ Model B · each arc is a residual, log(observed) − log(estimate).
Apps
31
Minutes
1,032
Goals
1
Assists
0
Started
8/31
Min / app
33
Cards
1Y 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 Petrov…

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 €500k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €500kModel A €631k

Asking 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

Hristiyan Petrov's percentiles among defenders: Goals per 90 82nd, Assists per 90 17th, Minutes, two years 13th, Starts 1st, Minutes, last 365 days 17th, European club minutes 30th82ndGoals17thAssists13thMinutes1stStarts17thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Goals per 90

Club goals per 90 minutes played in the two years to the valuation date.

0.09 this player0.03 defender median82nd percentile

0.00peer deciles · median line · this player ●0.41

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
€75k
Jan 2021
Peak
€1M
Jun 2024
Model target
€500k
May 2026
Valuations
15
2 club changes
May 2026€500kSC HeerenveenValuation the model is trained to reproduce

May 2026: €500k, SC Heerenveen. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2021-01-26€75kLitex Lovech
2021-06-17€150kLitex Lovech
2021-12-08€150kLitex Lovech
2022-05-31€150kCSKA-Sofia
2022-11-28€250kCSKA-Sofia
2023-06-05€500kCSKA-Sofia
2023-12-20€750kCSKA-Sofia
2024-03-19€850kCSKA-Sofia
2024-06-03€1MCSKA-Sofia
2024-09-10€900kCSKA-Sofia
2024-12-02€800kCSKA-Sofia
2025-03-28€600kSC Heerenveen
2025-05-28€600kSC Heerenveen
2025-12-02€500kSC Heerenveen
2026-05-28€500kSC Heerenveen

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
−0.232

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 25% of the 425 Eredivisie players.

€75k€500k€3M€20M€500kSee them in the Explorer →

Defenders, all leagues2,065 players · median €2M

Valued above 19% of the 2,065 defenders.

€20k€200k€2M€20M€500kSee them in the Explorer →

Where Petrov appears

Watchlists and the comparison tray are kept in this browser only.

Near this valuation closest observed values: same league, then same position

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).