FairValue

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

CBPortugal · GD Estoril Praia

№ 294321Emerging €1.1M −0.14

Player dossierLiga Portugal

Ferro

CBCentre-BackDefender

Club
GD Estoril Praia
League
Liga Portugal
Nationality
Portugal
Age
29
Height
191 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Ferro at €1M. Model A, which never saw Ferro during training, estimates €1.1M: the market value is 13% below that estimate.

That is a factor of ×1.15. 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 €1.6M, 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.

▼ −0.14A €1.1M▼ −0.50B €1.6M
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
45
Minutes
3,046
Goals
2
Assists
0
Started
33/45
Min / app
68
Cards
10Y 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 Ferro…

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 €1M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1MModel A €1.1M

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

Ferro's percentiles among defenders: Goals per 90 70th, Assists per 90 17th, Minutes, two years 53rd, Starts 32nd, Minutes, last 365 days 49th, European club minutes 30th70thGoals17thAssists53rdMinutes32ndStarts49thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Goals per 90

Club goals per 90 minutes played in the two years to the valuation date.

0.06 this player0.03 defender median70th percentile

0.00peer deciles · median line · this player ●0.41

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
€100k
Sept 2016
Peak
€18M
Dec 2019
Model target
€1M
May 2026
Valuations
27
8 club changes
May 2026€1MGD Estoril PraiaValuation the model is trained to reproduce

May 2026: €1M, GD Estoril Praia. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-09-30€100kSL Benfica B
2017-06-30€400kSL Benfica B
2017-09-08€400kSL Benfica B
2018-02-23€700kSL Benfica B
2018-06-29€1MSL Benfica B
2019-02-12€1.5MSL Benfica
2019-03-18€5MSL Benfica
2019-06-07€15MSL Benfica
2019-12-30€18MSL Benfica
2020-04-08€14.5MSL Benfica
2020-08-17€11MSL Benfica
2020-10-22€8MSL Benfica
2021-01-28€7MSL Benfica
2021-03-19€5MValencia CF
2021-06-10€5MValencia CF
2021-12-27€4MSL Benfica
2022-06-06€3.5MHNK Hajduk Split
2022-09-14€2.5MVitesse Arnhem
2022-11-11€2.5MVitesse Arnhem
2023-06-06€2MHNK Hajduk Split
2023-12-18€1.5MHNK Hajduk Split
2024-06-04€1MHNK Hajduk Split
2024-12-19€800kCF Estrela Amadora
2025-05-30€700kCF Estrela Amadora
2025-12-18€600kGD Estoril Praia
2026-03-19€800kGD Estoril Praia
2026-05-28€1MGD Estoril Praia

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
−0.136

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 42% of the 423 Liga Portugal players.

€20k€200k€2M€20M€1MSee them in the Explorer →

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

Valued above 35% of the 2,065 defenders.

€20k€200k€2M€20M€1MSee them in the Explorer →

Where Ferro 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).