FairValue

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

RBCape Verde · SC Farense

№ 975128Emerging €352k −0.57

Player dossierLiga Portugal

Rivaldo

RBRight-BackDefender

Club
SC Farense
League
Liga Portugal
Nationality
Cape Verde
Age
25
Height
184 cm
Foot
Right
Valued
22 Dec 2025

Reading the valuation

The market values Rivaldo at €200k. Model A, which never saw Rivaldo during training, estimates €352k: the market value is 43% below that estimate.

That is a factor of ×1.76. Model A's typical held-out miss is ×1.50 either way, so this gap is larger than its usual error.

Without league and club, Model B estimates €791k, 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.

▼ −0.57A €352k▼ −1.38B €791k
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
7
Minutes
451
Goals
0
Assists
1
Started
4/7
Min / app
64
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 Rivaldo…

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 €200k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €200kModel A €352k

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

Rivaldo's percentiles among defenders: Goals per 90 18th, Assists per 90 95th, Minutes, two years 0th, Starts 12th, Minutes, last 365 days 3rd, European club minutes 30th18thGoals95thAssists0thMinutes12thStarts3rdRecent30thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.20 this player0.04 defender median95th 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
€300k
Oct 2024
Peak
€300k
Oct 2024
Model target
€200k
Dec 2025
Valuations
4
0 club changes
Dec 2025€200kSC FarenseValuation the model is trained to reproduce

Dec 2025: €200k, SC Farense. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2024-10-08€300kSC Farense
2024-12-19€300kSC Farense
2025-05-30€200kSC Farense
2025-12-22€200kSC Farense

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
−0.566

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 5% of the 423 Liga Portugal players.

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

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

Valued above 5% of the 2,065 defenders.

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

Where Rivaldo 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).