FairValue

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Alexandre

Penetra

CBPortugal · AZ Alkmaar

№ 479643Elite €10.2M −0.02

Player dossierEredivisie

AlexandrePenetra

CBCentre-BackDefender

Club
AZ Alkmaar
League
Eredivisie
Nationality
Portugal
Age
24
Height
186 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Penetra at €10M. Model A, which never saw Penetra during training, estimates €10.2M: the market value is 2% below that estimate.

That is a factor of ×1.02. 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 €18.6M, 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.

▼ −0.02A €10.2M▼ −0.62B €18.6M
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
89
Minutes
7,671
Goals
2
Assists
1
Started
88/89
Min / app
86
Cards
11Y 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 Penetra…

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 €10M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €10MModel A €10.2M

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

Alexandre Penetra's percentiles among defenders: Goals per 90 43rd, Assists per 90 34th, Minutes, two years 99th, Starts 94th, Minutes, last 365 days 98th, European club minutes 83rd43rdGoals34thAssists99thMinutes94thStarts98thRecent83rdEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

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

7,671 this player2,860 defender median99th 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
€300k
Sept 2021
Peak
€10M
May 2026
Model target
€10M
May 2026
Valuations
14
1 club change
May 2026€10MAZ AlkmaarValuation the model is trained to reproduce

May 2026: €10M, AZ Alkmaar. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2021-09-21€300kFC Famalicão
2021-12-27€1MFC Famalicão
2022-03-10€2MFC Famalicão
2022-05-31€3MFC Famalicão
2022-11-01€3MFC Famalicão
2023-06-16€4MFC Famalicão
2023-12-15€5.5MAZ Alkmaar
2024-03-18€5MAZ Alkmaar
2024-05-31€4.5MAZ Alkmaar
2024-12-17€5MAZ Alkmaar
2025-03-28€7MAZ Alkmaar
2025-05-28€9MAZ Alkmaar
2025-12-02€9MAZ Alkmaar
2026-05-28€10MAZ Alkmaar

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
−0.025

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 →

Eredivisie425 players · median €1M

Valued above 91% of the 425 Eredivisie players.

€75k€500k€3M€20M€10MSee them in the Explorer →

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

Valued above 81% of the 2,065 defenders.

€20k€200k€2M€20M€10MSee them in the Explorer →

Where Penetra 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).