FairValue

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Leonidas

Stergiou

RBSwitzerland · 1.FC Heidenheim 1846

№ 507345Established €2M +0.20

Player dossierBundesliga

LeonidasStergiou

RBRight-BackDefender

Club
1.FC Heidenheim 1846
League
Bundesliga
Nationality
Switzerland
Age
24
Height
181 cm
Foot
Right
Valued
27 May 2026

Reading the valuation

The market values Stergiou at €2.5M. Model A, which never saw Stergiou during training, estimates €2M: the market value is 22% above that estimate.

That is a factor of ×1.22. 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 €1.8M, 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.

▲ +0.20A €2M▲ +0.33B €1.8M
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
25
Minutes
1,218
Goals
1
Assists
2
Started
13/25
Min / app
49
Cards
0Y 1R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Stergiou…

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 €2.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €2.5MModel A €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

Leonidas Stergiou's percentiles among defenders: Goals per 90 77th, Assists per 90 88th, Minutes, two years 16th, Starts 9th, Minutes, last 365 days 6th, European club minutes 65th77thGoals88thAssists16thMinutes9thStarts6thRecent65thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.15 this player0.04 defender median88th percentile

0.00peer deciles · median line · this player ●0.58

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
€750k
Apr 2019
Peak
€7M
Mar 2022
Model target
€2.5M
May 2026
Valuations
20
2 club changes
May 2026€2.5M1.FC Heidenheim 1846Valuation the model is trained to reproduce

May 2026: €2.5M, 1.FC Heidenheim 1846. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2019-04-15€750kFC St. Gallen 1879
2019-06-04€750kFC St. Gallen 1879
2020-01-06€2MFC St. Gallen 1879
2020-04-08€1.8MFC St. Gallen 1879
2020-07-31€2.5MFC St. Gallen 1879
2020-12-28€5MFC St. Gallen 1879
2021-06-23€6MFC St. Gallen 1879
2022-01-03€6MFC St. Gallen 1879
2022-03-28€7MFC St. Gallen 1879
2022-06-08€6MFC St. Gallen 1879
2022-11-10€4.5MFC St. Gallen 1879
2023-03-28€3.5MFC St. Gallen 1879
2023-06-07€3MFC St. Gallen 1879
2023-12-14€2MVfB Stuttgart
2024-05-29€5MVfB Stuttgart
2024-12-20€5MVfB Stuttgart
2025-06-05€5MVfB Stuttgart
2025-12-19€3.5MVfB Stuttgart
2026-03-20€3M1.FC Heidenheim 1846
2026-05-27€2.5M1.FC Heidenheim 1846

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
+0.200

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 25% of the 451 Bundesliga players.

€300k€2M€15M€100M€2.5MSee them in the Explorer →

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

Valued above 54% of the 2,065 defenders.

€20k€200k€2M€20M€2.5MSee them in the Explorer →

Where Stergiou 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).