FairValue

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

Mendyl

LBMorocco · Aris Thessaloniki

№ 447221Emerging €841k −0.05

Player dossierSuper League

HamzaMendyl

LBLeft-BackDefender

Club
Aris Thessaloniki
League
Super League
Nationality
Morocco
Age
28
Height
179 cm
Foot
Left
Valued
4 Jun 2026

Reading the valuation

The market values Mendyl at €800k. Model A, which never saw Mendyl during training, estimates €841k: the market value is 5% below that estimate.

That is a factor of ×1.05. 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 €1M, 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.

▼ −0.05A €841k▼ −0.27B €1M
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
30
Minutes
1,802
Goals
1
Assists
3
Started
21/30
Min / app
60
Cards
9Y 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 Mendyl…

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 €800k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €800kModel A €841k

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

Hamza Mendyl's percentiles among defenders: Goals per 90 64th, Assists per 90 88th, Minutes, two years 29th, Starts 27th, Minutes, last 365 days 15th, European club minutes 69th64thGoals88thAssists29thMinutes27thStarts15thRecent69thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.15 this player0.04 defender median88th 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
€250k
Nov 2016
Peak
€7M
Dec 2018
Model target
€800k
Jun 2026
Valuations
25
7 club changes
Jun 2026€800kAris ThessalonikiValuation the model is trained to reproduce

Jun 2026: €800k, Aris Thessaloniki. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-11-05€250kLOSC Lille B
2017-10-12€250kLOSC Lille
2018-01-24€600kLOSC Lille
2018-06-04€600kLOSC Lille
2018-08-22€6MFC Schalke 04
2018-12-18€7MFC Schalke 04
2019-06-05€4MFC Schalke 04
2019-12-19€3.5MDijon FCO
2020-04-08€2.8MDijon FCO
2021-02-10€1.8MFC Schalke 04
2021-06-09€1MFC Schalke 04
2021-10-12€1MGaziantep FK
2022-01-04€1MGaziantep FK
2022-03-31€1MGaziantep FK
2022-06-01€800kGaziantep FK
2022-11-04€800kOud-Heverlee Leuven
2023-06-09€1MOud-Heverlee Leuven
2023-10-23€1.5MOud-Heverlee Leuven
2023-12-19€1.8MOud-Heverlee Leuven
2024-03-22€1.3MOud-Heverlee Leuven
2024-06-04€1.3MOud-Heverlee Leuven
2024-12-11€1MOud-Heverlee Leuven
2025-05-23€1MAris Thessaloniki
2025-12-12€900kAris Thessaloniki
2026-06-04€800kAris Thessaloniki

Audit context group-level, not about this player

Audit group
non-UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
−0.050

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 60% of the 356 Super League players.

€20k€150k€1M€7.5M€800kSee them in the Explorer →

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

Valued above 29% of the 2,065 defenders.

€20k€200k€2M€20M€800kSee them in the Explorer →

Where Mendyl 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).