FairValue

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Giannis

Gianniotas

RWGreece · Aris Thessaloniki

№ 136643Emerging €549k −1.01

Player dossierSuper League

GiannisGianniotas

RWRight WingerAttack

Club
Aris Thessaloniki
League
Super League
Nationality
Greece
Age
33
Height
174 cm
Foot
Right
Valued
4 Jun 2026

Reading the valuation

The market values Gianniotas at €200k. Model A, which never saw Gianniotas during training, estimates €549k: the market value is 64% below that estimate.

That is a factor of ×2.75. 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 €646k, 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.

▼ −1.01A €549k▼ −1.17B €646k
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
43
Minutes
1,607
Goals
4
Assists
3
Started
12/43
Min / app
37
Cards
6Y 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 Gianniotas…

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 €200k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €200kModel A €549k

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 1,583 attackers

Giannis Gianniotas's percentiles among attackers: Goals per 90 42nd, Assists per 90 58th, Minutes, two years 35th, Starts 9th, Minutes, last 365 days 26th, European club minutes 67th42ndGoals58thAssists35thMinutes9thStarts26thRecent67thEurope

Dashed ring: the attacker median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

7% this player0% attacker median67th percentile

0%peer deciles · median line · this player ●100%

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
Jul 2011
Peak
€1.3M
May 2017
Model target
€200k
Jun 2026
Valuations
32
11 club changes
Jun 2026€200kAris ThessalonikiValuation the model is trained to reproduce

Jun 2026: €200k, Aris Thessaloniki. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2011-07-27€200kAris Thessaloniki
2011-11-21€200kAris Thessaloniki
2012-02-26€650kAris Thessaloniki
2012-09-21€850kAris Thessaloniki
2013-02-10€900kAris Thessaloniki
2014-01-20€900kFortuna Düsseldorf
2014-06-30€600kFortuna Düsseldorf
2014-11-11€600kAsteras Tripolis
2015-05-10€800kAsteras Tripolis
2015-09-27€800kOlympiacos Piraeus
2016-05-05€800kAPOEL Nicosia
2016-12-30€1MAPOEL Nicosia
2017-05-04€1.3MAPOEL Nicosia
2018-01-01€700kReal Valladolid CF
2018-05-30€700kReal Valladolid CF
2018-12-07€700kAEK Athens
2019-05-21€600kAEK Athens
2020-01-06€700kApollon Limassol
2020-04-08€550kApollon Limassol
2020-10-06€500kApollon Limassol
2021-05-14€600kApollon Limassol
2021-10-28€500kWithout Club
2022-06-09€300kApollon Smyrni
2022-11-07€250kLevadiakos
2023-05-22€250kLevadiakos
2023-12-28€300kLevadiakos
2024-03-13€350kLevadiakos
2024-05-23€350kLevadiakos
2024-12-18€300kLevadiakos
2025-05-23€250kLevadiakos
2025-12-12€250kAris Thessaloniki
2026-06-04€200kAris Thessaloniki

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
−1.011

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 10% of the 356 Super League players.

€20k€150k€1M€7.5M€200kSee them in the Explorer →

Attackers, all leagues1,583 players · median €2.5M

Valued above 4% of the 1,583 attackers.

€20k€300k€5M€75M€200kSee them in the Explorer →

Where Gianniotas 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).