FairValue

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

Pérez

RWSpain · Rayo Vallecano

№ 622988Established €5.5M −0.78

Player dossierLaLiga

FranPérez

RWRight WingerAttack

Club
Rayo Vallecano
League
LaLiga
Nationality
Spain
Age
23
Height
176 cm
Foot
Right
Valued
5 Jun 2026

Reading the valuation

The market values Pérez at €2.5M. Model A, which never saw Pérez during training, estimates €5.5M: the market value is 54% below that estimate.

That is a factor of ×2.19. 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 €4.9M, 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.

▼ −0.78A €5.5M▼ −0.67B €4.9M
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
64
Minutes
2,477
Goals
5
Assists
1
Started
25/64
Min / app
39
Cards
7Y 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 Pérez…

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 €2.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €2.5MModel A €5.5M

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

Fran Pérez's percentiles among attackers: Goals per 90 31st, Assists per 90 13th, Minutes, two years 56th, Starts 20th, Minutes, last 365 days 63rd, European club minutes 64th31stGoals13thAssists56thMinutes20thStarts63rdRecent64thEurope

Dashed ring: the attacker median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

5% this player0% attacker median64th 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
€100k
Dec 2020
Peak
€8M
Dec 2023
Model target
€2.5M
Jun 2026
Valuations
14
2 club changes
Jun 2026€2.5MRayo VallecanoValuation the model is trained to reproduce

Jun 2026: €2.5M, Rayo Vallecano. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-12-08€100kValencia Mestalla
2021-01-08€100kValencia Mestalla
2021-06-30€100kValencia Mestalla
2022-09-26€100kValencia Mestalla
2022-12-29€150kValencia Mestalla
2023-06-30€500kValencia Mestalla
2023-10-13€5MValencia CF
2023-12-22€8MValencia CF
2024-06-07€8MValencia CF
2024-10-11€6MValencia CF
2024-12-27€4MValencia CF
2025-06-09€3MValencia CF
2025-12-12€3MRayo Vallecano
2026-06-05€2.5MRayo Vallecano

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
−0.783

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 →

LaLiga509 players · median €4M

Valued above 34% of the 509 LaLiga players.

€100k€1M€10M€100M€2.5MSee them in the Explorer →

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

Valued above 48% of the 1,583 attackers.

€20k€300k€5M€75M€2.5MSee them in the Explorer →

Where Pérez 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).