FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Portrait of Javi López

Javi

López

LBSpain · Real Oviedo

№ 568158Established €4M +0.23

Close-up

Image: FootyLogos

Player dossierLaLiga

JaviLópez

LBLeft-BackDefender

Club
Real Oviedo
League
LaLiga
Nationality
Spain
Age
24
Height
183 cm
Foot
Left
Valued
5 Jun 2026

Reading the valuation

The market values López at €5M. Model A, which never saw López during training, estimates €4M: the market value is 26% above that estimate.

That is a factor of ×1.26. 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 €6.4M, 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.

▲ +0.23A €4M▼ −0.24B €6.4M
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
4,189
Goals
0
Assists
1
Started
45/64
Min / app
65
Cards
8Y 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 López…

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 €5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €5MModel A €4M

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

Javi López's percentiles among defenders: Goals per 90 18th, Assists per 90 38th, Minutes, two years 72nd, Starts 27th, Minutes, last 365 days 53rd, European club minutes 70th18thGoals38thAssists72ndMinutes27thStarts53rdRecent70thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

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

4,189 this player2,860 defender median72nd 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
€50k
Sept 2019
Peak
€7.5M
Jun 2024
Model target
€5M
Jun 2026
Valuations
17
3 club changes
Jun 2026€5MReal OviedoValuation the model is trained to reproduce

Jun 2026: €5M, Real Oviedo. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2019-09-10€50kDeportivo Alavés B
2020-02-11€250kDeportivo Alavés B
2020-10-08€600kDeportivo Alavés
2021-01-05€600kDeportivo Alavés
2021-06-10€600kDeportivo Alavés
2021-12-30€800kDeportivo Alavés
2022-06-03€700kDeportivo Alavés
2022-12-29€700kDeportivo Alavés
2023-06-14€700kDeportivo Alavés
2023-10-13€1MDeportivo Alavés
2023-12-22€3MDeportivo Alavés
2024-03-21€5MDeportivo Alavés
2024-06-07€7.5MDeportivo Alavés
2024-12-27€7.5MReal Sociedad
2025-06-09€7.5MReal Sociedad
2025-12-12€5MReal Oviedo
2026-06-05€5MReal Oviedo

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
+0.234

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 57% of the 509 LaLiga players.

€100k€1M€10M€100M€5MSee them in the Explorer →

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

Valued above 70% of the 2,065 defenders.

€20k€200k€2M€20M€5MSee them in the Explorer →

Where López 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).