FairValue

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

Costa

CFPortugal · SC Farense

№ 451858Emerging €501k 0.00

Player dossierLiga Portugal

RuiCosta

CFCentre-ForwardAttack

Club
SC Farense
League
Liga Portugal
Nationality
Portugal
Age
29
Height
179 cm
Foot
Right
Valued
22 Dec 2025

Reading the valuation

The market values Costa at €500k. Model A, which never saw Costa during training, estimates €501k: the market value is level with that estimate.

That is a factor of ×1.00. 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 €619k, 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.

▼ 0.00A €501k▼ −0.21B €619k
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
26
Minutes
992
Goals
2
Assists
1
Started
7/26
Min / app
38
Cards
1Y 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 Costa…

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 €500k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €500kModel A €501k

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

Rui Costa's percentiles among attackers: Goals per 90 31st, Assists per 90 28th, Minutes, two years 19th, Starts 8th, Minutes, last 365 days 24th, European club minutes 76th31stGoals28thAssists19thMinutes8thStarts24thRecent76thEurope

Dashed ring: the attacker median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

14% this player0% attacker median76th percentile

0%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
€25k
Sept 2016
Peak
€800k
Sept 2023
Model target
€500k
Dec 2025
Valuations
22
9 club changes
Dec 2025€500kSC FarenseValuation the model is trained to reproduce

Dec 2025: €500k, SC Farense. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-09-30€25kVarzim SC
2017-06-30€600kVarzim SC
2017-09-08€350kFC Famalicão
2018-02-07€750kPortimonense SAD
2018-06-13€750kPortimonense SAD
2019-02-12€550kFC Porto B
2019-06-29€500kFC Porto B
2019-12-20€500kAD Alcorcón
2020-04-08€400kAD Alcorcón
2020-10-08€400kDeportivo de La Coruña
2021-01-07€400kDeportivo de La Coruña
2021-05-21€500kCD Santa Clara
2021-12-27€600kCD Santa Clara
2022-05-31€600kCD Santa Clara
2022-12-28€550kSC Farense
2023-06-28€550kSC Farense
2023-09-29€800kSC Farense
2023-12-27€700kSC Farense
2024-06-06€500kSC Farense
2024-11-14€550kTobol Kostanay
2025-05-30€600kSC Farense
2025-12-22€500kSC Farense

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
−0.003

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 20% of the 423 Liga Portugal players.

€20k€200k€2M€20M€500kSee them in the Explorer →

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

Valued above 15% of the 1,583 attackers.

€20k€300k€5M€75M€500kSee them in the Explorer →

Where Costa 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).