FairValue

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

Mário

AMPortugal · AEK Athens

№ 149729Emerging €1.6M −0.07

Player dossierSuper League

JoãoMário

AMAttacking MidfieldMidfield

Club
AEK Athens
League
Super League
Nationality
Portugal
Age
33
Height
179 cm
Foot
Right
Valued
4 Jun 2026

Reading the valuation

The market values Mário at €1.5M. Model A, which never saw Mário during training, estimates €1.6M: the market value is 7% below that estimate.

That is a factor of ×1.08. 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 €1.1M, 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.

▼ −0.07A €1.6M▲ +0.34B €1.1M
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
68
Minutes
3,826
Goals
11
Assists
6
Started
41/68
Min / app
56
Cards
4Y 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 Mário…

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 €1.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1.5MModel A €1.6M

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 1,687 midfielders

João Mário's percentiles among midfielders: Goals per 90 90th, Assists per 90 68th, Minutes, two years 71st, Starts 35th, Minutes, last 365 days 59th, European club minutes 79th90thGoals68thAssists71stMinutes35thStarts59thRecent79thEurope

Dashed ring: the midfielder median (50th percentile)

Goals per 90

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

0.26 this player0.08 midfielder median90th percentile

0.00peer deciles · median line · this player ●0.93

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
€1.4M
Nov 2012
Peak
€35M
Oct 2016
Model target
€1.5M
Jun 2026
Valuations
37
9 club changes
Jun 2026€1.5MAEK AthensValuation the model is trained to reproduce

Jun 2026: €1.5M, AEK Athens. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2012-11-10€1.4MSporting CP B
2013-03-28€2MSporting CP B
2014-07-25€3MSporting CP
2015-02-17€6.5MSporting CP
2015-07-01€8MSporting CP
2016-02-24€12MSporting CP
2016-06-01€20MSporting CP
2016-07-29€30MSporting CP
2016-10-14€35MInter Milan
2017-01-02€35MInter Milan
2017-06-08€30MInter Milan
2017-12-29€26MInter Milan
2018-05-28€25MWest Ham United
2018-07-16€23MInter Milan
2018-10-12€20MInter Milan
2018-12-20€20MInter Milan
2019-06-06€18MInter Milan
2019-12-23€18MLokomotiv Moscow
2020-04-08€14.5MLokomotiv Moscow
2020-07-29€13MLokomotiv Moscow
2021-01-28€13MSporting CP
2021-05-21€12MSporting CP
2021-12-27€14MSL Benfica
2022-03-10€12MSL Benfica
2022-05-31€10MSL Benfica
2022-11-01€12MSL Benfica
2023-03-02€14MSL Benfica
2023-06-16€14MSL Benfica
2023-12-27€9MSL Benfica
2024-03-08€6MSL Benfica
2024-06-06€4MSL Benfica
2024-10-04€3.8MBesiktas JK
2024-12-23€2.8MBesiktas JK
2025-03-20€2.3MBesiktas JK
2025-06-18€2.1MBesiktas JK
2025-12-12€1.8MAEK Athens
2026-06-04€1.5MAEK Athens

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
−0.073

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 →

Super League356 players · median €600k

Valued above 73% of the 356 Super League players.

€20k€150k€1M€7.5M€1.5MSee them in the Explorer →

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

Valued above 39% of the 1,687 midfielders.

€20k€200k€2M€20M€1.5MSee them in the Explorer →

Where Mário 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).