FairValue

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Portrait of Konstantinos Koulierakis

Konstantinos

Koulierakis

CBGreece · VfL Wolfsburg

№ 669380Elite €10.3M +0.89

Close-up

Image: FootyLogos

Player dossierBundesliga

KonstantinosKoulierakis

CBCentre-BackDefender

Club
VfL Wolfsburg
League
Bundesliga
Nationality
Greece
Age
22
Height
188 cm
Foot
Left
Valued
27 May 2026

Reading the valuation

The market values Koulierakis at €25M. Model A, which never saw Koulierakis during training, estimates €10.3M: the market value is 143% above that estimate.

That is a factor of ×2.43. 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 €8.9M, 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.

▲ +0.89A €10.3M▲ +1.03B €8.9M
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
69
Minutes
5,880
Goals
7
Assists
4
Started
65/69
Min / app
85
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 Koulierakis…

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 €25M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €25MModel A €10.3M

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 Koulierakis's percentiles among defenders: Goals per 90 89th, Assists per 90 63rd, Minutes, two years 92nd, Starts 82nd, Minutes, last 365 days 79th, European club minutes 70th89thGoals63rdAssists92ndMinutes82ndStarts79thRecent70thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

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

5,880 this player2,860 defender median92nd 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
€175k
Dec 2021
Peak
€25M
Jun 2025
Model target
€25M
May 2026
Valuations
16
2 club changes
May 2026€25MVfL WolfsburgValuation the model is trained to reproduce

May 2026: €25M, VfL Wolfsburg. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2021-12-28€175kPAOK Thessaloniki B
2022-02-22€250kPAOK Thessaloniki B
2022-06-27€300kPAOK Thessaloniki B
2022-11-07€1.5MPAOK Thessaloniki
2023-02-27€2MPAOK Thessaloniki
2023-05-22€2.5MPAOK Thessaloniki
2023-09-21€3MPAOK Thessaloniki
2023-12-20€4.5MPAOK Thessaloniki
2024-03-06€6MPAOK Thessaloniki
2024-05-30€8MPAOK Thessaloniki
2024-10-09€12MVfL Wolfsburg
2024-12-20€15MVfL Wolfsburg
2025-03-27€20MVfL Wolfsburg
2025-06-05€25MVfL Wolfsburg
2025-12-19€25MVfL Wolfsburg
2026-05-27€25MVfL Wolfsburg

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
+0.889

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 →

Bundesliga451 players · median €5M

Valued above 87% of the 451 Bundesliga players.

€300k€2M€15M€100M€25MSee them in the Explorer →

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

Valued above 93% of the 2,065 defenders.

€20k€200k€2M€20M€25MSee them in the Explorer →

Where Koulierakis 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).