FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Portrait of Zeki Çelik

Zeki

Çelik

RBTürkiye · AS Roma

№ 251075Elite €15.2M −0.08

Close-up

Image: FootyLogos

Player dossierSerie A

ZekiÇelik

RBRight-BackDefender

Club
AS Roma
League
Serie A
Nationality
Türkiye
Age
29
Height
180 cm
Foot
Right
Valued
29 May 2026

Reading the valuation

The market values Çelik at €14M. Model A, which never saw Çelik during training, estimates €15.2M: the market value is 8% below that estimate.

That is a factor of ×1.09. 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 €16.1M, 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.

▼ −0.08A €15.2M▼ −0.14B €16.1M
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
88
Minutes
6,810
Goals
2
Assists
7
Started
81/88
Min / app
77
Cards
12Y 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 Çelik…

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 €14M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €14MModel A €15.2M

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

Zeki Çelik's percentiles among defenders: Goals per 90 45th, Assists per 90 75th, Minutes, two years 97th, Starts 76th, Minutes, last 365 days 97th, European club minutes 89th45thGoals75thAssists97thMinutes76thStarts97thRecent89thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

Total club minutes in the two-year window: how much the player was used.

6,810 this player2,860 defender median97th percentile

451peer deciles · median line · this player ●9,111

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
Jul 2014
Peak
€20M
Dec 2019
Model target
€14M
May 2026
Valuations
29
3 club changes
May 2026€14MAS RomaValuation the model is trained to reproduce

May 2026: €14M, AS Roma. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2014-07-20€100kBursaspor U19
2016-09-01€200kIstanbulspor
2017-06-30€250kIstanbulspor
2018-02-05€350kIstanbulspor
2018-04-09€700kIstanbulspor
2018-05-30€800kIstanbulspor
2018-09-06€2MLOSC Lille
2018-10-24€4MLOSC Lille
2018-12-17€6MLOSC Lille
2019-03-07€10MLOSC Lille
2019-06-03€17MLOSC Lille
2019-12-19€20MLOSC Lille
2020-04-08€16MLOSC Lille
2020-10-15€20MLOSC Lille
2021-05-25€20MLOSC Lille
2021-12-16€17MLOSC Lille
2022-03-23€18MLOSC Lille
2022-05-30€18MLOSC Lille
2022-09-27€15MAS Roma
2022-11-11€15MAS Roma
2023-03-21€10MAS Roma
2023-06-15€10MAS Roma
2023-10-11€8MAS Roma
2023-12-20€6MAS Roma
2024-06-05€6MAS Roma
2024-12-18€5MAS Roma
2025-06-17€6MAS Roma
2025-12-23€12MAS Roma
2026-05-29€14MAS Roma

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
−0.083

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 →

Serie A507 players · median €5.5M

Valued above 73% of the 507 Serie A players.

€100k€750k€5M€30M€14MSee them in the Explorer →

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

Valued above 86% of the 2,065 defenders.

€20k€200k€2M€20M€14MSee them in the Explorer →

Where Çelik 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).