FairValue

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

González

CMSpain · US Lecce

№ 692209Emerging €3.3M −1.41

Player dossierSerie A

JoanGonzález

CMCentral MidfieldMidfield

Club
US Lecce
League
Serie A
Nationality
Spain
Age
23
Height
190 cm
Foot
Right
Valued
17 Jun 2025

Reading the valuation

The market values González at €800k. Model A, which never saw González during training, estimates €3.3M: the market value is 76% below that estimate.

That is a factor of ×4.11. 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 €1.3M, closer to the market here, although it is usually further off (typical miss ×2.07).

A gap describes the model's arithmetic for this player's inputs, not what the player is worth.

▼ −1.41A €3.3M▼ −0.51B €1.3M
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
30
Minutes
1,372
Goals
1
Assists
1
Started
14/30
Min / app
46
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 González…

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 €800k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €800kModel A €3.3M

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 1,687 midfielders

Joan González's percentiles among midfielders: Goals per 90 42nd, Assists per 90 37th, Minutes, two years 22nd, Starts 17th, Minutes, last 365 days 1st, European club minutes 30th42ndGoals37thAssists22ndMinutes17thStarts1stRecent30thEurope

Dashed ring: the midfielder median (50th percentile)

Goals per 90

Club goals per 90 minutes played in the two years to the valuation date.

0.07 this player0.08 midfielder median42nd percentile

0.00peer deciles · median line · this player ●0.93

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
€250k
Jun 2022
Peak
€6M
Mar 2023
Model target
€800k
Jun 2025
Valuations
11
1 club change
Jun 2025€800kUS LecceValuation the model is trained to reproduce

Jun 2025: €800k, US Lecce. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2022-06-23€250kLecce Primavera
2022-09-27€1.4MUS Lecce
2022-11-11€3MUS Lecce
2023-03-21€6MUS Lecce
2023-06-15€6MUS Lecce
2023-12-20€6MUS Lecce
2024-03-12€5MUS Lecce
2024-06-05€4.5MUS Lecce
2024-12-18€2MUS Lecce
2025-03-25€800kUS Lecce
2025-06-17€800kUS Lecce

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
−1.413

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 →

Serie A507 players · median €5.5M

Valued above 4% of the 507 Serie A players.

€100k€750k€5M€30M€800kSee them in the Explorer →

Midfielders, all leagues1,687 players · median €2M

Valued above 27% of the 1,687 midfielders.

€20k€200k€2M€20M€800kSee them in the Explorer →

Where González 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).