FairValue

Checking model

Esc

  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
  • EnvironmentTerminalExplore, compare and track players; market, league and model views.
  • EnvironmentStoriesValuations, head-to-heads and research findings, told as stories.
  • TerminalPlayer ExplorerSearch, filter and sort the player export.
  • TerminalComparison StudioTwo to four players on one scale.
  • TerminalWatchlistsNamed collections, kept in this browser.
  • TerminalMarket LandscapeHow observed value is distributed, and where the model drifts.

↑ ↓ to move · Enter to open · Esc to closeLoading player index…

Léo

Pétrot

CBFrance · Elche CF

№ 412829Emerging €3.3M −0.78

Player dossierLaLiga

LéoPétrot

CBCentre-BackDefender

Club
Elche CF
League
LaLiga
Nationality
France
Age
29
Height
188 cm
Foot
Left
Valued
5 Jun 2026

Reading the valuation

The market values Pétrot at €1.5M. Model A, which never saw Pétrot during training, estimates €3.3M: 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 €5.7M, 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.

▼ −0.78A €3.3M▼ −1.34B €5.7M
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
67
Minutes
4,522
Goals
1
Assists
3
Started
50/67
Min / app
67
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 Pétrot…

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 €1.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1.5MModel A €3.3M

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

Léo Pétrot's percentiles among defenders: Goals per 90 40th, Assists per 90 63rd, Minutes, two years 77th, Starts 34th, Minutes, last 365 days 58th, European club minutes 30th40thGoals63rdAssists77thMinutes34thStarts58thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

Total club minutes in the two-year window: how much the player was used.

4,522 this player2,860 defender median77th percentile

451peer deciles · median line · this player ●9,111

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
€300k
Oct 2021
Peak
€1.5M
Dec 2025
Model target
€1.5M
Jun 2026
Valuations
13
2 club changes
Jun 2026€1.5MElche CFValuation the model is trained to reproduce

Jun 2026: €1.5M, Elche CF. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2021-10-08€300kFC Lorient
2021-12-16€800kFC Lorient
2022-03-23€1MFC Lorient
2022-05-30€1MFC Lorient
2022-10-28€700kAS Saint-Étienne
2023-06-16€900kAS Saint-Étienne
2023-12-13€900kAS Saint-Étienne
2024-03-26€800kAS Saint-Étienne
2024-06-11€1MAS Saint-Étienne
2024-12-10€1MAS Saint-Étienne
2025-06-03€900kAS Saint-Étienne
2025-12-12€1.5MElche CF
2026-06-05€1.5MElche CF

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
−0.784

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 20% of the 509 LaLiga players.

€100k€1M€10M€100M€1.5MSee them in the Explorer →

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

Valued above 43% of the 2,065 defenders.

€20k€200k€2M€20M€1.5MSee them in the Explorer →

Where Pétrot 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).