FairValue

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

Costa

CBBrazil · FC Krasnodar

№ 546212Elite €7.5M +0.47

Player dossierPremier Liga

DiegoCosta

CBCentre-BackDefender

Club
FC Krasnodar
League
Premier Liga
Nationality
Brazil
Age
26
Height
184 cm
Foot
Right
Valued
26 May 2026

Reading the valuation

The market values Costa at €12M. Model A, which never saw Costa during training, estimates €7.5M: the market value is 60% above that estimate.

That is a factor of ×1.60. 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 €3.3M, 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.

▲ +0.47A €7.5M▲ +1.28B €3.3M
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
68
Minutes
5,786
Goals
4
Assists
0
Started
62/68
Min / app
85
Cards
17Y 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 €12M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €12MModel A €7.5M

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

Diego Costa's percentiles among defenders: Goals per 90 71st, Assists per 90 17th, Minutes, two years 91st, Starts 73rd, Minutes, last 365 days 90th, European club minutes 30th71stGoals17thAssists91stMinutes73rdStarts90thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

Total club minutes in the two-year window: how much the player was used.

5,786 this player2,860 defender median91st percentile

451peer deciles · median line · this player ●9,111

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
€1.8M
Sept 2020
Peak
€12M
May 2026
Model target
€12M
May 2026
Valuations
17
1 club change
May 2026€12MFC KrasnodarValuation the model is trained to reproduce

May 2026: €12M, FC Krasnodar. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-09-09€1.8MSão Paulo Futebol Clube
2021-02-09€1.8MSão Paulo Futebol Clube
2021-05-28€1.8MSão Paulo Futebol Clube
2021-12-17€1.8MSão Paulo Futebol Clube
2022-04-06€2.5MSão Paulo Futebol Clube
2022-08-19€2.5MSão Paulo Futebol Clube
2022-11-14€3MSão Paulo Futebol Clube
2023-04-07€4MSão Paulo Futebol Clube
2023-07-25€4MSão Paulo Futebol Clube
2023-12-11€4MSão Paulo Futebol Clube
2024-03-28€4MSão Paulo Futebol Clube
2024-06-17€3.5MSão Paulo Futebol Clube
2024-09-18€6MFC Krasnodar
2024-12-12€7MFC Krasnodar
2025-06-04€8MFC Krasnodar
2025-12-16€10MFC Krasnodar
2026-05-26€12MFC Krasnodar

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
+0.469

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 →

Premier Liga412 players · median €1M

Valued above 96% of the 412 Premier Liga players.

€50k€300k€2M€15M€12MSee them in the Explorer →

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

Valued above 84% of the 2,065 defenders.

€20k€200k€2M€20M€12MSee 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).