FairValue

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Portrait of Fábio Vieira

Fábio

Vieira

AMPortugal · Hamburger SV

№ 537598Elite €9.8M +0.61

Image: FootyLogos

Player dossierBundesliga

FábioVieira

AMAttacking MidfieldMidfield

Club
Hamburger SV
League
Bundesliga
Nationality
Portugal
Age
25
Height
170 cm
Foot
Left
Valued
27 May 2026

Reading the valuation

The market values Vieira at €18M. Model A, which never saw Vieira during training, estimates €9.8M: the market value is 84% above that estimate.

That is a factor of ×1.84. 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 €7.1M, 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.

▲ +0.61A €9.8M▲ +0.94B €7.1M
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
71
Minutes
4,970
Goals
12
Assists
12
Started
55/71
Min / app
70
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 Vieira…

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 €18M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €18MModel A €9.8M

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 1,687 midfielders

Fábio Vieira's percentiles among midfielders: Goals per 90 85th, Assists per 90 87th, Minutes, two years 86th, Starts 66th, Minutes, last 365 days 84th, European club minutes 76th85thGoals87thAssists86thMinutes66thStarts84thRecent76thEurope

Dashed ring: the midfielder median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.22 this player0.09 midfielder median87th percentile

0.00peer deciles · median line · this player ●0.74

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
€700k
Dec 2019
Peak
€30M
Sept 2022
Model target
€18M
May 2026
Valuations
20
4 club changes
May 2026€18MHamburger SVValuation the model is trained to reproduce

May 2026: €18M, Hamburger SV. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2019-12-31€700kFC Porto B
2020-04-08€625kFC Porto B
2020-08-17€7MFC Porto
2021-01-28€9MFC Porto
2021-05-21€9MFC Porto
2021-12-27€10MFC Porto
2022-03-10€17MFC Porto
2022-05-31€25MFC Porto
2022-09-15€30MArsenal FC
2022-11-03€30MArsenal FC
2023-03-16€27MArsenal FC
2023-06-20€25MArsenal FC
2023-12-19€28MArsenal FC
2024-03-14€25MArsenal FC
2024-05-27€22MArsenal FC
2024-12-19€22MFC Porto
2025-05-30€22MFC Porto
2025-10-14€18MHamburger SV
2025-12-19€18MHamburger SV
2026-05-27€18MHamburger SV

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
+0.609

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 →

Bundesliga451 players · median €5M

Valued above 80% of the 451 Bundesliga players.

€300k€2M€15M€100M€18MSee them in the Explorer →

Midfielders, all leagues1,687 players · median €2M

Valued above 87% of the 1,687 midfielders.

€20k€200k€2M€20M€18MSee them in the Explorer →

Where Vieira 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).