FairValue

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

Martínez

LBSpain · Moreirense FC

№ 718577Emerging €542k −0.30

Player dossierLiga Portugal

ÁlvaroMartínez

LBLeft-BackDefender

Club
Moreirense FC
League
Liga Portugal
Nationality
Spain
Age
24
Height
181 cm
Foot
Left
Valued
28 May 2026

Reading the valuation

The market values Martínez at €400k. Model A, which never saw Martínez during training, estimates €542k: the market value is 26% below that estimate.

That is a factor of ×1.35. 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 €552k, 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.

▼ −0.30A €542k▼ −0.32B €552k
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
15
Minutes
812
Goals
0
Assists
0
Started
9/15
Min / app
54
Cards
1Y 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 Martínez…

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 €400k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €400kModel A €542k

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

Álvaro Martínez's percentiles among defenders: Goals per 90 18th, Assists per 90 17th, Minutes, two years 7th, Starts 15th, Minutes, last 365 days 23rd, European club minutes 30th18thGoals17thAssists7thMinutes15thStarts23rdRecent30thEurope

Dashed ring: the defender median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

0% this player0% defender median30th 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
€50k
Aug 2021
Peak
€400k
Jun 2025
Model target
€400k
May 2026
Valuations
14
4 club changes
May 2026€400kMoreirense FCValuation the model is trained to reproduce

May 2026: €400k, Moreirense FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2021-08-12€50kBetis Deportivo Balompié
2021-12-30€50kClub Lleida Esportiu
2022-06-29€50kBetis Deportivo Balompié
2022-12-29€50kBetis Deportivo Balompié
2023-06-30€50kBetis Deportivo Balompié
2023-10-13€100kCultural Leonesa
2023-12-20€100kCultural Leonesa
2024-06-24€150kCultural Leonesa
2024-10-14€200kCultural Leonesa
2024-12-18€200kCultural Leonesa
2025-03-27€300kCultural Leonesa
2025-06-25€400kCultural Leonesa
2025-12-18€400kMoreirense FC
2026-05-28€400kMoreirense FC

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
−0.304

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 →

Liga Portugal423 players · median €1M

Valued above 12% of the 423 Liga Portugal players.

€20k€200k€2M€20M€400kSee them in the Explorer →

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

Valued above 14% of the 2,065 defenders.

€20k€200k€2M€20M€400kSee them in the Explorer →

Where Martínez 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).