FairValue

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Aritz

Elustondo

CBSpain · Real Sociedad

№ 229804Emerging €1.6M −0.05

Player dossierLaLiga

AritzElustondo

CBCentre-BackDefender

Club
Real Sociedad
League
LaLiga
Nationality
Spain
Age
32
Height
180 cm
Foot
Right
Valued
5 Jun 2026

Reading the valuation

The market values Elustondo at €1.5M. Model A, which never saw Elustondo during training, estimates €1.6M: the market value is 5% below that estimate.

That is a factor of ×1.05. 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 €2.6M, 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.

▼ −0.05A €1.6M▼ −0.55B €2.6M
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
55
Minutes
3,143
Goals
0
Assists
2
Started
33/55
Min / app
57
Cards
5Y 1R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Elustondo…

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 €1.6M

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 2,065 defenders

Aritz Elustondo's percentiles among defenders: Goals per 90 18th, Assists per 90 62nd, Minutes, two years 55th, Starts 15th, Minutes, last 365 days 25th, European club minutes 84th18thGoals62ndAssists55thMinutes15thStarts25thRecent84thEurope

Dashed ring: the defender median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

20% this player0% defender median84th 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
€400k
Jul 2015
Peak
€20M
Dec 2021
Model target
€1.5M
Jun 2026
Valuations
28
1 club change
Jun 2026€1.5MReal SociedadValuation the model is trained to reproduce

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

Show as a table
DateMarket valueClub
2015-07-01€400kReal Sociedad B
2016-02-22€2MReal Sociedad
2016-07-15€5MReal Sociedad
2017-01-24€3MReal Sociedad
2017-06-05€2.5MReal Sociedad
2018-01-01€2.5MReal Sociedad
2018-05-30€5MReal Sociedad
2018-12-21€7.5MReal Sociedad
2019-06-11€10MReal Sociedad
2019-12-20€10MReal Sociedad
2020-04-08€8MReal Sociedad
2020-10-08€10MReal Sociedad
2020-11-23€15MReal Sociedad
2021-01-05€15MReal Sociedad
2021-06-10€15MReal Sociedad
2021-10-13€18MReal Sociedad
2021-12-30€20MReal Sociedad
2022-06-03€20MReal Sociedad
2022-11-07€14MReal Sociedad
2023-06-13€14MReal Sociedad
2023-10-13€10MReal Sociedad
2023-12-22€9MReal Sociedad
2024-06-07€5MReal Sociedad
2024-12-27€4MReal Sociedad
2025-06-09€3MReal Sociedad
2025-10-02€2MReal Sociedad
2025-12-12€1.8MReal Sociedad
2026-06-05€1.5MReal Sociedad

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
−0.049

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 Elustondo 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).