FairValue

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Portrait of Konstantinos Mavropanos

Konstantinos

Mavropanos

CBGreece · West Ham United

№ 415912Elite €15.9M +0.13

Image: FootyLogos

Player dossierPremier League

KonstantinosMavropanos

CBCentre-BackDefender

Club
West Ham United
League
Premier League
Nationality
Greece
Age
28
Height
194 cm
Foot
Right
Valued
3 Jun 2026

Reading the valuation

The market values Mavropanos at €18M. Model A, which never saw Mavropanos during training, estimates €15.9M: the market value is 13% above 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 €14.1M, 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.

▲ +0.13A €15.9M▲ +0.25B €14.1M
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
70
Minutes
5,074
Goals
3
Assists
0
Started
53/70
Min / app
72
Cards
8Y 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 Mavropanos…

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 €18M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €18MModel A €15.9M

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

Konstantinos Mavropanos's percentiles among defenders: Goals per 90 66th, Assists per 90 17th, Minutes, two years 84th, Starts 36th, Minutes, last 365 days 87th, European club minutes 30th66thGoals17thAssists84thMinutes36thStarts87thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, last 365 days

Club minutes in the final year of the window: recent involvement, or the absence of it.

2,907 this player1,687 defender median87th percentile

0peer deciles · median line · this player ●4,941

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
Feb 2016
Peak
€20M
May 2024
Model target
€18M
Jun 2026
Valuations
26
4 club changes
Jun 2026€18MWest Ham UnitedValuation the model is trained to reproduce

Jun 2026: €18M, West Ham United. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-02-21€75kPAS Giannina
2016-06-21€100kPAS Giannina
2016-12-21€100kPAS Giannina
2017-05-11€100kPAS Giannina
2017-12-18€450kPAS Giannina
2018-03-23€2MArsenal FC
2018-05-28€3MArsenal FC
2018-12-19€3MArsenal FC
2019-06-13€3MArsenal FC
2019-12-10€3MArsenal FC
2020-04-08€2.4M1.FC Nuremberg
2021-02-10€2.5MVfB Stuttgart
2021-03-31€6MVfB Stuttgart
2021-06-09€6MVfB Stuttgart
2021-12-22€17MVfB Stuttgart
2022-06-09€15MVfB Stuttgart
2022-11-09€15MVfB Stuttgart
2023-06-22€15MVfB Stuttgart
2023-12-19€14MWest Ham United
2024-03-14€18MWest Ham United
2024-05-27€20MWest Ham United
2024-12-16€20MWest Ham United
2025-03-18€17MWest Ham United
2025-05-30€17MWest Ham United
2025-12-09€15MWest Ham United
2026-06-03€18MWest Ham United

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
+0.125

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 →

Premier League555 players · median €18M

Valued above 50% of the 555 Premier League players.

€150k€1M€7.5M€50M€18MSee them in the Explorer →

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

Valued above 89% of the 2,065 defenders.

€20k€200k€2M€20M€18MSee them in the Explorer →

Where Mavropanos 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).