FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Portrait of Idrissa Gueye

Idrissa

Gueye

CFSenegal · Udinese Calcio

№ 1178488Established €3.6M +0.79

Image: FootyLogos

Player dossierSerie A

IdrissaGueye

CFCentre-ForwardAttack

Club
Udinese Calcio
League
Serie A
Nationality
Senegal
Age
19
Height
185 cm
Foot
Right
Valued
29 May 2026

Reading the valuation

The market values Gueye at €8M. Model A, which never saw Gueye during training, estimates €3.6M: the market value is 120% above that estimate.

That is a factor of ×2.20. 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 €1.2M, 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.

▲ +0.79A €3.6M▲ +1.92B €1.2M
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
24
Minutes
575
Goals
1
Assists
0
Started
2/24
Min / app
24
Cards
2Y 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 Gueye…

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 €8M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €8MModel A €3.6M

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

Idrissa Gueye's percentiles among attackers: Goals per 90 25th, Assists per 90 6th, Minutes, two years 4th, Starts 0th, Minutes, last 365 days 18th, European club minutes 28th25thGoals6thAssists4thMinutes0thStarts18thRecent28thEurope

Dashed ring: the attacker median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

0% this player0% attacker median28th percentile

0%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
€1.5M
Mar 2025
Peak
€8M
May 2026
Model target
€8M
May 2026
Valuations
4
1 club change
May 2026€8MUdinese CalcioValuation the model is trained to reproduce

May 2026: €8M, Udinese Calcio. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2025-03-12€1.5MFC Metz
2025-06-02€4MFC Metz
2025-12-23€4MUdinese Calcio
2026-05-29€8MUdinese Calcio

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
+0.789

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 →

Serie A507 players · median €5.5M

Valued above 60% of the 507 Serie A players.

€100k€750k€5M€30M€8MSee them in the Explorer →

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

Valued above 74% of the 1,583 attackers.

€20k€300k€5M€75M€8MSee them in the Explorer →

Where Gueye 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).