FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Portrait of Lucas Stassin

Lucas

Stassin

CFBelgium · AS Saint-Étienne

№ 655012Elite €7.9M +0.65

Image: FootyLogos

Player dossierLigue 1

LucasStassin

CFCentre-ForwardAttack

Club
AS Saint-Étienne
League
Ligue 1
Nationality
Belgium
Age
21
Height
183 cm
Foot
Right
Valued
11 Dec 2025

Reading the valuation

The market values Stassin at €15M. Model A, which never saw Stassin during training, estimates €7.9M: the market value is 91% above that estimate.

That is a factor of ×1.91. 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 €6.3M, 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.

▲ +0.65A €7.9M▲ +0.87B €6.3M
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
35
Minutes
2,303
Goals
16
Assists
8
Started
28/35
Min / app
66
Cards
5Y 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 Stassin…

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 €15M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €15MModel A €7.9M

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

Lucas Stassin's percentiles among attackers: Goals per 90 96th, Assists per 90 92nd, Minutes, two years 52nd, Starts 83rd, Minutes, last 365 days 54th, European club minutes 28th96thGoals92ndAssists52ndMinutes83rdStarts54thRecent28thEurope

Dashed ring: the attacker median (50th percentile)

Goals per 90

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

0.63 this player0.26 attacker median96th percentile

0.00peer deciles · median line · this player ●1.17

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
€450k
Oct 2022
Peak
€18M
Jun 2025
Model target
€15M
Dec 2025
Valuations
12
2 club changes
Dec 2025€15MAS Saint-ÉtienneValuation the model is trained to reproduce

Dec 2025: €15M, AS Saint-Étienne. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2022-10-05€450kRSCA Futures
2022-11-04€1MRSCA Futures
2023-05-30€1.2MRSCA Futures
2023-10-23€1.5MKVC Westerlo
2023-12-19€1.5MKVC Westerlo
2024-06-04€3MKVC Westerlo
2024-10-07€6MAS Saint-Étienne
2024-12-10€5MAS Saint-Étienne
2025-03-24€7MAS Saint-Étienne
2025-06-03€18MAS Saint-Étienne
2025-10-13€16MAS Saint-Étienne
2025-12-11€15MAS Saint-Étienne

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
+0.647

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 →

Ligue 1423 players · median €5M

Valued above 76% of the 423 Ligue 1 players.

€100k€750k€5M€30M€15MSee them in the Explorer →

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

Valued above 81% of the 1,583 attackers.

€20k€300k€5M€75M€15MSee them in the Explorer →

Where Stassin 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).