FairValue

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

Marques

LWPortugal · Casa Pia AC

№ 891971Emerging €1.1M +0.31

Player dossierLiga Portugal

JoãoMarques

LWLeft WingerAttack

Club
Casa Pia AC
League
Liga Portugal
Nationality
Portugal
Age
24
Height
179 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Marques at €1.5M. Model A, which never saw Marques during training, estimates €1.1M: the market value is 36% above that estimate.

That is a factor of ×1.36. 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.

▲ +0.31A €1.1M▲ +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
31
Minutes
1,229
Goals
1
Assists
3
Started
12/31
Min / app
40
Cards
7Y 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 Marques…

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 €1.1M

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 1,583 attackers

João Marques's percentiles among attackers: Goals per 90 10th, Assists per 90 76th, Minutes, two years 25th, Starts 19th, Minutes, last 365 days 19th, European club minutes 58th10thGoals76thAssists25thMinutes19thStarts19thRecent58thEurope

Dashed ring: the attacker median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.22 this player0.15 attacker median76th percentile

0.00peer deciles · median line · this player ●0.73

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
€250k
Jun 2021
Peak
€3.5M
Mar 2024
Model target
€1.5M
May 2026
Valuations
11
6 club changes
May 2026€1.5MCasa Pia ACValuation the model is trained to reproduce

May 2026: €1.5M, Casa Pia AC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2021-06-29€250kVitória Setúbal FC
2023-03-02€300kEstoril Praia U23
2023-06-16€300kEstoril Praia U23
2023-09-29€1MGD Estoril Praia
2023-12-27€2.5MGD Estoril Praia
2024-03-08€3.5MGD Estoril Praia
2024-06-06€3.5MGD Estoril Praia
2024-12-19€3MSC Braga
2025-05-30€3MGil Vicente FC
2025-12-18€1.5MSC Braga
2026-05-28€1.5MCasa Pia AC

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
+0.305

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 53% of the 423 Liga Portugal players.

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

Attackers, all leagues1,583 players · median €2.5M

Valued above 37% of the 1,583 attackers.

€20k€300k€5M€75M€1.5MSee them in the Explorer →

Where Marques 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).