FairValue

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

Graça

CMPortugal · Rio Ave FC

№ 257707Emerging €222k +0.30

Player dossierLiga Portugal

JoãoGraça

CMCentral MidfieldMidfield

Club
Rio Ave FC
League
Liga Portugal
Nationality
Portugal
Age
30
Height
177 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Graça at €300k. Model A, which never saw Graça during training, estimates €222k: the market value is 35% above that estimate.

That is a factor of ×1.35. 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 €453k, 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.

▲ +0.30A €222k▼ −0.41B €453k
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
24
Minutes
545
Goals
1
Assists
0
Started
3/24
Min / app
23
Cards
2Y 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 Graça…

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 €300k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €300kModel A €222k

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 Graça's percentiles among midfielders: Goals per 90 75th, Assists per 90 8th, Minutes, two years 2nd, Starts 1st, Minutes, last 365 days 3rd, European club minutes 30th75thGoals8thAssists2ndMinutes1stStarts3rdRecent30thEurope

Dashed ring: the midfielder median (50th percentile)

Goals per 90

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

0.17 this player0.08 midfielder median75th 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
€250k
Jul 2015
Peak
€800k
Sept 2016
Model target
€300k
May 2026
Valuations
22
6 club changes
May 2026€300kRio Ave FCValuation the model is trained to reproduce

May 2026: €300k, Rio Ave FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2015-07-31€250kFC Porto B
2016-03-14€500kFC Porto B
2016-09-30€800kFC Porto B
2017-06-30€750kFC Porto B
2018-02-07€500kCD Feirense
2018-06-13€200kCD Feirense
2019-01-11€100kFC Arouca
2019-06-29€100kUD Oliveirense
2019-12-31€225kLeixões SC
2020-11-02€125kCD Mafra
2021-06-29€200kCD Mafra
2022-04-01€175kRio Ave FC
2022-06-27€200kRio Ave FC
2022-11-01€200kRio Ave FC
2023-03-02€400kRio Ave FC
2023-06-16€400kRio Ave FC
2023-12-27€400kRio Ave FC
2024-06-06€500kRio Ave FC
2024-12-19€300kRio Ave FC
2025-05-30€300kRio Ave FC
2025-12-18€300kRio Ave FC
2026-05-28€300kRio Ave FC

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
+0.303

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 8% of the 423 Liga Portugal players.

€20k€200k€2M€20M€300kSee them in the Explorer →

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

Valued above 7% of the 1,687 midfielders.

€20k€200k€2M€20M€300kSee them in the Explorer →

Where Graça 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).