FairValue

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

Rocha

CBUruguay · FC Arouca

№ 821824Emerging €590k −0.39

Player dossierLiga Portugal

MatíasRocha

CBCentre-BackDefender

Club
FC Arouca
League
Liga Portugal
Nationality
Uruguay
Age
25
Height
183 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Rocha at €400k. Model A, which never saw Rocha during training, estimates €590k: the market value is 32% below that estimate.

That is a factor of ×1.48. 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 €616k, 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.

▼ −0.39A €590k▼ −0.43B €616k
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
16
Minutes
1,143
Goals
0
Assists
0
Started
12/16
Min / app
71
Cards
6Y 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 Rocha…

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 €400k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €400kModel A €590k

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

Matías Rocha's percentiles among defenders: Goals per 90 18th, Assists per 90 17th, Minutes, two years 15th, Starts 35th, Minutes, last 365 days 24th, European club minutes 30th18thGoals17thAssists15thMinutes35thStarts24thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Starts

Share of appearances started rather than entered from the bench.

75% this player83% defender median35th percentile

18%peer deciles · median line · this player ●100%

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
€200k
Apr 2021
Peak
€500k
Jun 2024
Model target
€400k
May 2026
Valuations
12
1 club change
May 2026€400kFC AroucaValuation the model is trained to reproduce

May 2026: €400k, FC Arouca. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2021-04-10€200kDefensor Sporting Club
2021-09-10€300kDefensor Sporting Club
2022-01-01€350kDefensor Sporting Club
2022-06-02€450kDefensor Sporting Club
2022-11-12€450kDefensor Sporting Club
2023-07-10€450kDefensor Sporting Club
2023-12-27€400kFC Arouca
2024-06-06€500kFC Arouca
2024-12-19€500kFC Arouca
2025-05-30€400kFC Arouca
2025-12-18€400kFC Arouca
2026-05-28€400kFC Arouca

Audit context group-level, not about this player

Audit group
non-UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
−0.389

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 12% of the 423 Liga Portugal players.

€20k€200k€2M€20M€400kSee them in the Explorer →

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

Valued above 14% of the 2,065 defenders.

€20k€200k€2M€20M€400kSee them in the Explorer →

Where Rocha 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).