FairValue

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

Lewis

LBUruguay · OFI Crete FC

№ 584427Emerging €349k +0.25

Player dossierSuper League

KevinLewis

LBLeft-BackDefender

Club
OFI Crete FC
League
Super League
Nationality
Uruguay
Age
26
Height
173 cm
Foot
Left
Valued
12 Dec 2025

Reading the valuation

The market values Lewis at €450k. Model A, which never saw Lewis during training, estimates €349k: the market value is 29% above that estimate.

That is a factor of ×1.29. 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 €640k, 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.

▲ +0.25A €349k▼ −0.35B €640k
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
16
Minutes
640
Goals
0
Assists
0
Started
7/16
Min / app
40
Cards
6Y 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 Lewis…

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 €450k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €450kModel A €349k

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

Kevin Lewis's percentiles among defenders: Goals per 90 18th, Assists per 90 17th, Minutes, two years 4th, Starts 4th, Minutes, last 365 days 16th, European club minutes 30th18thGoals17thAssists4thMinutes4thStarts16thRecent30thEurope

Dashed ring: the defender median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

0% this player0% defender median30th 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
€50k
Feb 2019
Peak
€800k
Jun 2024
Model target
€450k
Dec 2025
Valuations
16
6 club changes
Dec 2025€450kOFI Crete FCValuation the model is trained to reproduce

Dec 2025: €450k, OFI Crete FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2019-02-10€50kUnknown
2019-03-03€75kUnknown
2019-12-25€75kUnknown
2021-01-02€100kCA Peñarol
2021-04-10€100kCA Peñarol
2021-09-10€200kIA Sud América
2022-01-01€200kCA Peñarol
2022-06-10€150kCA Peñarol
2022-11-12€250kAlbion FC
2023-07-10€400kDanubio FC
2023-12-28€700kDanubio FC
2024-06-10€800kDanubio FC
2024-12-19€650kDanubio FC
2025-03-14€600kOFI Crete FC
2025-05-23€500kOFI Crete FC
2025-12-12€450kOFI Crete FC

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
+0.253

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 35% of the 356 Super League players.

€20k€150k€1M€7.5M€450kSee them in the Explorer →

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

Valued above 17% of the 2,065 defenders.

€20k€200k€2M€20M€450kSee them in the Explorer →

Where Lewis 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).