FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Marios

Tsaousis

LBGreece · Panserraikos

№ 416465Emerging €547k −0.09

Player dossierSuper League

MariosTsaousis

LBLeft-BackDefender

Club
Panserraikos
League
Super League
Nationality
Greece
Age
26
Height
175 cm
Foot
Left
Valued
4 Jun 2026

Reading the valuation

The market values Tsaousis at €500k. Model A, which never saw Tsaousis during training, estimates €547k: the market value is 9% 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 €725k, 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.

▼ −0.09A €547k▼ −0.37B €725k
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
24
Minutes
1,845
Goals
0
Assists
1
Started
20/24
Min / app
77
Cards
1Y 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 Tsaousis…

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 €500k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €500kModel A €547k

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

Marios Tsaousis's percentiles among defenders: Goals per 90 18th, Assists per 90 56th, Minutes, two years 30th, Starts 52nd, Minutes, last 365 days 56th, European club minutes 30th18thGoals56thAssists30thMinutes52ndStarts56thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.05 this player0.04 defender median56th 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
€200k
Sept 2019
Peak
€600k
Nov 2022
Model target
€500k
Jun 2026
Valuations
17
7 club changes
Jun 2026€500kPanserraikosValuation the model is trained to reproduce

Jun 2026: €500k, Panserraikos. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2019-09-23€200kVolos NFC
2019-12-18€200kVolos NFC
2020-08-04€200kPAOK Thessaloniki
2020-12-28€200kSpartak Trnava
2021-06-26€200kSpartak Trnava
2021-12-28€200kPAOK Thessaloniki B
2022-06-27€250kPAOK Thessaloniki B
2022-11-07€600kPAOK Thessaloniki
2023-05-22€600kPAOK Thessaloniki
2023-12-20€600kPAS Giannina
2024-03-06€500kPAS Giannina
2024-05-30€500kPAS Giannina
2024-09-24€450kPAOK Thessaloniki B
2024-12-27€450kPAOK Thessaloniki B
2025-05-16€450kPAOK Thessaloniki B
2025-12-12€450kPanserraikos
2026-06-04€500kPanserraikos

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
−0.090

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 →

Super League356 players · median €600k

Valued above 43% of the 356 Super League players.

€20k€150k€1M€7.5M€500kSee them in the Explorer →

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

Valued above 19% of the 2,065 defenders.

€20k€200k€2M€20M€500kSee them in the Explorer →

Where Tsaousis 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).