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Nikolaos

Kaltsas

RWGreece · Asteras Aktor

№ 73700Emerging €164k −0.27

Player dossierSuper League

NikolaosKaltsas

RWRight WingerAttack

Club
Asteras Aktor
League
Super League
Nationality
Greece
Age
36
Height
172 cm
Foot
Right
Valued
4 Jun 2026

Reading the valuation

The market values Kaltsas at €125k. Model A, which never saw Kaltsas during training, estimates €164k: the market value is 24% below that estimate.

That is a factor of ×1.31. 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 €229k, 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.

▼ −0.27A €164k▼ −0.60B €229k
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
55
Minutes
3,746
Goals
9
Assists
2
Started
42/55
Min / app
68
Cards
14Y 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 Kaltsas…

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 €125k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €125kModel A €164k

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

Nikolaos Kaltsas's percentiles among attackers: Goals per 90 40th, Assists per 90 15th, Minutes, two years 77th, Starts 78th, Minutes, last 365 days 59th, European club minutes 28th40thGoals15thAssists77thMinutes78thStarts59thRecent28thEurope

Dashed ring: the attacker median (50th percentile)

Starts

Share of appearances started rather than entered from the bench.

76% this player59% attacker median78th percentile

5%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
€150k
Apr 2008
Peak
€1M
Feb 2016
Model target
€125k
Jun 2026
Valuations
36
6 club changes
Jun 2026€125kAsteras AktorValuation the model is trained to reproduce

Jun 2026: €125k, Asteras Aktor. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2008-04-22€150kPAE Veria
2010-09-27€250kPAE Veria
2010-11-16€150kPAE Veria
2011-06-30€350kPAE Veria
2011-11-07€350kPAE Veria
2011-12-29€400kPAE Veria
2012-09-21€400kPAE Veria
2013-02-10€450kPAE Veria
2013-12-02€500kPAE Veria
2014-03-28€500kPAE Veria
2014-11-11€600kPAE Veria
2015-05-10€900kPAE Veria
2015-09-27€900kPanathinaikos
2016-02-21€1MPanathinaikos
2016-06-21€900kPanathinaikos
2016-12-21€800kAsteras Tripolis
2017-05-11€700kAsteras Tripolis
2017-12-18€700kAsteras Tripolis
2018-05-22€750kAsteras Tripolis
2018-12-07€600kAsteras Tripolis
2019-05-21€600kAsteras Tripolis
2020-01-06€700kAnorthosis Famagusta
2020-04-08€550kAnorthosis Famagusta
2020-10-06€700kAnorthosis Famagusta
2021-05-14€700kAnorthosis Famagusta
2022-01-11€600kAnorthosis Famagusta
2022-06-20€500kAnorthosis Famagusta
2023-01-10€400kKarmiotissa Pano Polemidion
2023-05-31€400kKarmiotissa Pano Polemidion
2023-09-21€350kAsteras Tripolis
2023-12-20€350kAsteras Tripolis
2024-05-30€300kAsteras Tripolis
2024-12-18€250kAsteras Aktor
2025-05-23€200kAsteras Aktor
2025-12-12€175kAsteras Aktor
2026-06-04€125kAsteras Aktor

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
−0.272

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 3% of the 356 Super League players.

€20k€150k€1M€7.5M€125kSee them in the Explorer →

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

Valued above 2% of the 1,583 attackers.

€20k€300k€5M€75M€125kSee them in the Explorer →

Where Kaltsas 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).