FairValue

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

Romão

LBBrazil · CD Santa Clara

№ 519879Emerging €570k −0.35

Player dossierLiga Portugal

GuilhermeRomão

LBLeft-BackDefender

Club
CD Santa Clara
League
Liga Portugal
Nationality
Brazil
Age
28
Height
176 cm
Foot
Left
Valued
28 May 2026

Reading the valuation

The market values Romão at €400k. Model A, which never saw Romão during training, estimates €570k: the market value is 30% below that estimate.

That is a factor of ×1.42. 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 €753k, 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.

▼ −0.35A €570k▼ −0.63B €753k
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
12
Minutes
890
Goals
0
Assists
1
Started
10/12
Min / app
74
Cards
0Y 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 Romão…

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 €570k

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

Guilherme Romão's percentiles among defenders: Goals per 90 18th, Assists per 90 77th, Minutes, two years 9th, Starts 52nd, Minutes, last 365 days 25th, European club minutes 30th18thGoals77thAssists9thMinutes52ndStarts25thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.10 this player0.04 defender median77th percentile

0.00peer deciles · median line · this player ●0.58

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
€400k
Oct 2017
Peak
€450k
Dec 2021
Model target
€400k
May 2026
Valuations
14
5 club changes
May 2026€400kCD Santa ClaraValuation the model is trained to reproduce

May 2026: €400k, CD Santa Clara. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2017-10-30€400kOeste FC
2017-12-07€400kSC Corinthians B
2020-04-08€325kBotafogo FC
2021-08-12€400kClube de Regatas Brasil (AL)
2021-12-03€450kClube de Regatas Brasil (AL)
2022-08-05€400kClube de Regatas Brasil (AL)
2023-07-18€400kClube de Regatas Brasil (AL)
2023-11-27€400kClube de Regatas Brasil (AL)
2024-03-28€400kAtlético Clube Goianiense
2024-06-17€400kAtlético Clube Goianiense
2024-12-09€400kAtlético Clube Goianiense
2025-06-27€400kAtlético Clube Goianiense
2025-11-24€400kAtlético Clube Goianiense
2026-05-28€400kCD Santa Clara

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
−0.353

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 Romão 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).