FairValue

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Ertuğrul

Ersoy

CBTürkiye · Bursaspor

№ 251079Emerging €631k −0.74

Player dossierSüper Lig

ErtuğrulErsoy

CBCentre-BackDefender

Club
Bursaspor
League
Süper Lig
Nationality
Türkiye
Age
28
Height
187 cm
Foot
Right
Valued
5 Jan 2026

Reading the valuation

The market values Ersoy at €300k. Model A, which never saw Ersoy during training, estimates €631k: the market value is 52% below that estimate.

That is a factor of ×2.10. Model A's typical held-out miss is ×1.50 either way, so this gap is larger than its usual error.

Without league and club, Model B estimates €1.1M, 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.

▼ −0.74A €631k▼ −1.28B €1.1M
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
2,098
Goals
2
Assists
0
Started
26/31
Min / app
68
Cards
5Y 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 Ersoy…

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 €300k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €300kModel 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

Ertuğrul Ersoy's percentiles among defenders: Goals per 90 82nd, Assists per 90 17th, Minutes, two years 36th, Starts 53rd, Minutes, last 365 days 2nd, European club minutes 30th82ndGoals17thAssists36thMinutes53rdStarts2ndRecent30thEurope

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
€200k
May 2014
Peak
€3M
Jan 2019
Model target
€300k
Jan 2026
Valuations
34
9 club changes
Jan 2026€300kBursasporValuation the model is trained to reproduce

Jan 2026: €300k, Bursaspor. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2014-05-18€200kYesil Bursa SK
2015-01-26€500kBursaspor
2015-06-25€900kBursaspor
2016-01-18€1.5MCaykur Rizespor
2016-07-15€1.2MBursaspor
2017-01-10€1.5MBursaspor
2017-06-09€1.5MBursaspor
2018-02-12€1.8MBursaspor
2018-05-29€1.8MBursaspor
2018-10-11€2.3MBursaspor
2019-01-04€3MBursaspor
2019-06-04€2.5MBursaspor
2019-09-30€1.5MLe Havre AC
2020-01-06€1.5MLe Havre AC
2020-04-08€1.2MLe Havre AC
2020-11-11€1.2MLe Havre AC
2021-03-16€1.2MGaziantep FK
2021-05-21€1MGaziantep FK
2021-10-12€750kGaziantep FK
2022-01-04€675kGaziantep FK
2022-03-31€650kGaziantep FK
2022-06-01€600kGaziantep FK
2022-10-27€750kGaziantep FK
2023-03-14€750kIstanbulspor
2023-06-08€750kIstanbulspor
2023-09-27€700kGaziantep FK
2023-12-21€500kGaziantep FK
2024-03-15€625kGaziantep FK
2024-05-31€650kGaziantep FK
2024-10-04€600kGaziantep FK
2024-12-23€600kGaziantep FK
2025-03-20€500kGaziantep FK
2025-06-02€200kWithout Club
2026-01-05€300kBursaspor

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
−0.744

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 →

Süper Lig428 players · median €1.2M

Valued above 12% of the 428 Süper Lig players.

€50k€300k€2M€15M€300kSee them in the Explorer →

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

Valued above 9% of the 2,065 defenders.

€20k€200k€2M€20M€300kSee them in the Explorer →

Where Ersoy 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).