FairValue

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Giannis

Kosti

CMCyprus · Levadiakos

№ 435288Emerging €1.7M −0.36

Player dossierSuper League

GiannisKosti

CMCentral MidfieldMidfield

Club
Levadiakos
League
Super League
Nationality
Cyprus
Age
26
Height
170 cm
Foot
Right
Valued
4 Jun 2026

Reading the valuation

The market values Kosti at €1.2M. Model A, which never saw Kosti during training, estimates €1.7M: the market value is 30% below that estimate.

That is a factor of ×1.43. 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 €1.6M, closer to the market here, although it is usually further off (typical miss ×2.07).

A gap describes the model's arithmetic for this player's inputs, not what the player is worth.

▼ −0.36A €1.7M▼ −0.28B €1.6M
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
54
Minutes
3,962
Goals
7
Assists
1
Started
45/54
Min / app
73
Cards
18Y 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 Kosti…

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 €1.2M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1.2MModel A €1.7M

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 1,687 midfielders

Giannis Kosti's percentiles among midfielders: Goals per 90 74th, Assists per 90 18th, Minutes, two years 73rd, Starts 76th, Minutes, last 365 days 77th, European club minutes 30th74thGoals18thAssists73rdMinutes76thStarts77thRecent30thEurope

Dashed ring: the midfielder median (50th percentile)

Minutes, last 365 days

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

2,422 this player1,541 midfielder median77th percentile

0peer deciles · median line · this player ●4,800

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
€25k
Nov 2017
Peak
€1.2M
Jun 2026
Model target
€1.2M
Jun 2026
Valuations
22
4 club changes
Jun 2026€1.2MLevadiakosValuation the model is trained to reproduce

Jun 2026: €1.2M, Levadiakos. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2017-11-13€25kNea Salamina Famagusta
2018-04-26€100kNea Salamina Famagusta
2018-12-31€250kNea Salamina Famagusta
2019-06-25€350kNea Salamina Famagusta
2019-09-24€700kNea Salamina Famagusta
2020-01-06€700kNea Salamina Famagusta
2020-04-08€625kNea Salamina Famagusta
2020-10-12€600kAE Larisa
2021-02-12€400kLevadiakos
2021-05-21€450kLevadiakos
2021-12-28€450kOlympiacos Piraeus B
2022-06-27€500kOlympiacos Piraeus B
2023-02-27€450kOlympiacos Piraeus B
2023-06-19€450kOlympiacos Piraeus B
2023-12-28€450kOlympiacos Piraeus B
2024-03-13€400kLevadiakos
2024-05-23€400kLevadiakos
2024-12-18€400kLevadiakos
2025-05-23€500kLevadiakos
2025-12-12€600kLevadiakos
2026-03-06€1MLevadiakos
2026-06-04€1.2MLevadiakos

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
−0.358

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 69% of the 356 Super League players.

€20k€150k€1M€7.5M€1.2MSee them in the Explorer →

Midfielders, all leagues1,687 players · median €2M

Valued above 35% of the 1,687 midfielders.

€20k€200k€2M€20M€1.2MSee them in the Explorer →

Where Kosti 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).