FairValue

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Nikolaos

Karelis

CFGreece · Panserraikos

№ 63487Emerging €151k +0.50

Player dossierSuper League

NikolaosKarelis

CFCentre-ForwardAttack

Club
Panserraikos
League
Super League
Nationality
Greece
Age
34
Height
173 cm
Foot
Left
Valued
4 Jun 2026

Reading the valuation

The market values Karelis at €250k. Model A, which never saw Karelis during training, estimates €151k: the market value is 66% above that estimate.

That is a factor of ×1.66. 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 €247k, 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.

▲ +0.50A €151k▲ +0.01B €247k
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
18
Minutes
544
Goals
0
Assists
2
Started
4/18
Min / app
30
Cards
0Y 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 Karelis…

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 €250k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €250kModel A €151k

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 Karelis's percentiles among attackers: Goals per 90 3rd, Assists per 90 94th, Minutes, two years 3rd, Starts 5th, Minutes, last 365 days 17th, European club minutes 28th3rdGoals94thAssists3rdMinutes5thStarts17thRecent28thEurope

Dashed ring: the attacker median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.33 this player0.15 attacker median94th percentile

0.00peer deciles · median line · this player ●0.73

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
Dec 2008
Peak
€4.5M
Jan 2017
Model target
€250k
Jun 2026
Valuations
40
9 club changes
Jun 2026€250kPanserraikosValuation the model is trained to reproduce

Jun 2026: €250k, Panserraikos. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2008-12-20€200kErgotelis FC
2009-11-02€300kErgotelis FC
2010-01-18€300kErgotelis FC
2010-09-21€350kErgotelis FC
2011-02-22€400kErgotelis FC
2011-06-30€500kErgotelis FC
2011-11-14€500kErgotelis FC
2012-02-26€400kErgotelis FC
2013-01-27€400kAmkar Perm
2013-06-24€400kAmkar Perm
2014-03-28€600kPanathinaikos
2014-11-11€1.5MPanathinaikos
2015-05-10€2.5MPanathinaikos
2015-09-27€3.8MPanathinaikos
2016-02-07€3.8MKRC Genk
2016-04-14€4MKRC Genk
2016-07-15€4MKRC Genk
2017-01-21€4.5MKRC Genk
2017-06-06€4.5MKRC Genk
2018-01-09€4MKRC Genk
2018-06-03€3MKRC Genk
2018-12-07€2MPAOK Thessaloniki
2019-02-07€1.5MPAOK Thessaloniki
2019-05-21€1.3MPAOK Thessaloniki
2020-02-27€1MBrentford FC
2020-04-08€800kBrentford FC
2020-10-14€800kADO Den Haag
2021-02-12€600kPanetolikos
2021-11-01€500kPanetolikos
2022-02-22€600kPanetolikos
2022-06-09€600kPanetolikos
2022-11-07€800kPanetolikos
2023-05-22€800kPanetolikos
2023-12-20€700kPanetolikos
2024-03-06€600kPanetolikos
2024-05-30€500kPanetolikos
2024-12-13€500kMumbai City FC
2025-05-30€450kMumbai City FC
2025-12-12€350kPanserraikos
2026-06-04€250kPanserraikos

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
+0.504

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 15% of the 356 Super League players.

€20k€150k€1M€7.5M€250kSee them in the Explorer →

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

Valued above 6% of the 1,583 attackers.

€20k€300k€5M€75M€250kSee them in the Explorer →

Where Karelis 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).