FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Portrait of Myles Lewis-Skelly

Myles

Lewis-Skelly

LBEngland · Arsenal FC

№ 890721World Class €54.9M −0.20

Image: FootyLogos

Player dossierPremier League

MylesLewis-Skelly

LBLeft-BackDefender

Club
Arsenal FC
League
Premier League
Nationality
England
Age
19
Height
178 cm
Foot
Left
Valued
3 Jun 2026

Reading the valuation

The market values Lewis-Skelly at €45M. Model A, which never saw Lewis-Skelly during training, estimates €54.9M: the market value is 18% below that estimate.

That is a factor of ×1.22. 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 €30.1M, 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.

▼ −0.20A €54.9M▲ +0.40B €30.1M
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
69
Minutes
3,845
Goals
1
Assists
6
Started
41/69
Min / app
56
Cards
11Y 2R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Lewis-Skelly…

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 €45M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €45MModel A €54.9M

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

Myles Lewis-Skelly's percentiles among defenders: Goals per 90 43rd, Assists per 90 86th, Minutes, two years 67th, Starts 15th, Minutes, last 365 days 55th, European club minutes 96th43rdGoals86thAssists67thMinutes15thStarts55thRecent96thEurope

Dashed ring: the defender median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

31% this player0% defender median96th percentile

0%peer deciles · median line · this player ●85%

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
€2M
Dec 2023
Peak
€45M
May 2025
Model target
€45M
Jun 2026
Valuations
8
1 club change
Jun 2026€45MArsenal FCValuation the model is trained to reproduce

Jun 2026: €45M, Arsenal FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2023-12-19€2MArsenal FC U21
2024-10-01€5MArsenal FC
2024-12-16€10MArsenal FC
2025-03-18€28MArsenal FC
2025-05-30€45MArsenal FC
2025-12-09€40MArsenal FC
2026-03-09€35MArsenal FC
2026-06-03€45MArsenal FC

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
−0.199

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 →

Premier League555 players · median €18M

Valued above 86% of the 555 Premier League players.

€150k€1M€7.5M€50M€45MSee them in the Explorer →

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

Valued above 98% of the 2,065 defenders.

€20k€200k€2M€20M€45MSee them in the Explorer →

Where Lewis-Skelly 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).