FairValue

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

Fernandes

RBPortugal · FC Porto

№ 935480Elite €21.6M −0.59

Player dossierLiga Portugal

MartimFernandes

RBRight-BackDefender

Club
FC Porto
League
Liga Portugal
Nationality
Portugal
Age
20
Height
181 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Fernandes at €12M. Model A, which never saw Fernandes during training, estimates €21.6M: the market value is 45% below that estimate.

That is a factor of ×1.80. 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 €15.2M, 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.

▼ −0.59A €21.6M▼ −0.24B €15.2M
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
65
Minutes
3,585
Goals
1
Assists
8
Started
40/65
Min / app
55
Cards
9Y 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 Fernandes…

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 €12M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €12MModel A €21.6M

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

Martim Fernandes's percentiles among defenders: Goals per 90 44th, Assists per 90 95th, Minutes, two years 63rd, Starts 17th, Minutes, last 365 days 53rd, European club minutes 90th44thGoals95thAssists63rdMinutes17thStarts53rdRecent90thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.20 this player0.04 defender median95th percentile

0.00peer deciles · median line · this player ●0.58

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
Dec 2022
Peak
€12M
May 2025
Model target
€12M
May 2026
Valuations
10
1 club change
May 2026€12MFC PortoValuation the model is trained to reproduce

May 2026: €12M, FC Porto. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2022-12-28€300kFC Porto B
2023-06-28€500kFC Porto B
2023-12-14€1MFC Porto B
2024-06-06€4MFC Porto
2024-10-08€6MFC Porto
2024-12-19€8MFC Porto
2025-03-31€10MFC Porto
2025-05-30€12MFC Porto
2025-12-18€12MFC Porto
2026-05-28€12MFC Porto

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
−0.590

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 88% of the 423 Liga Portugal players.

€20k€200k€2M€20M€12MSee them in the Explorer →

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

Valued above 84% of the 2,065 defenders.

€20k€200k€2M€20M€12MSee them in the Explorer →

Where Fernandes 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).