FairValue

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Donovan

Léon

GKFrench Guiana · AJ Auxerre

№ 170911Emerging €1.6M −0.71

Player dossierLigue 1

DonovanLéon

GKGoalkeeperGoalkeeper

Club
AJ Auxerre
League
Ligue 1
Nationality
French Guiana
Age
33
Height
187 cm
Foot
Right
Valued
1 Jun 2026

Reading the valuation

The market values Léon at €800k. Model A, which never saw Léon during training, estimates €1.6M: the market value is 51% below that estimate.

That is a factor of ×2.04. 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 €1.7M, 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.

▼ −0.71A €1.6M▼ −0.73B €1.7M
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
61
Minutes
5,343
Started
61/61
Min / app
88
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 Léon…

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 €1.6M

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 485 goalkeepers

Donovan Léon's percentiles among goalkeepers: Minutes, two years 80th, Starts 62nd, Minutes, last 365 days 67th, European club minutes 32nd80thMinutes62ndStarts67thRecent32ndEurope

Dashed ring: the goalkeeper median (50th percentile)

Minutes, two years

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

5,343 this player2,790 goalkeeper median80th percentile

450peer deciles · median line · this player ●9,210

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
€50k
Jul 2011
Peak
€1.2M
Jun 2022
Model target
€800k
Jun 2026
Valuations
34
2 club changes
Jun 2026€800kAJ AuxerreValuation the model is trained to reproduce

Jun 2026: €800k, AJ Auxerre. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2011-07-20€50kAJ Auxerre
2011-09-27€300kAJ Auxerre
2011-12-24€400kAJ Auxerre
2012-05-23€400kAJ Auxerre
2012-09-05€750kAJ Auxerre
2013-01-04€750kAJ Auxerre
2013-05-29€750kAJ Auxerre
2014-01-13€500kAJ Auxerre
2014-11-20€800kAJ Auxerre
2015-06-06€800kAJ Auxerre
2016-02-04€600kStade Brestois 29
2016-07-13€300kStade Brestois 29
2017-03-20€300kStade Brestois 29
2017-06-15€300kStade Brestois 29
2018-05-16€250kStade Brestois 29
2019-01-08€250kStade Brestois 29
2019-06-27€250kStade Brestois 29
2019-12-19€400kStade Brestois 29
2020-04-08€325kStade Brestois 29
2020-08-14€400kAJ Auxerre
2020-11-11€600kAJ Auxerre
2021-06-25€600kAJ Auxerre
2021-12-27€800kAJ Auxerre
2022-06-02€1.2MAJ Auxerre
2022-09-19€800kAJ Auxerre
2022-11-02€600kAJ Auxerre
2023-06-27€500kAJ Auxerre
2023-12-13€500kAJ Auxerre
2024-06-11€500kAJ Auxerre
2024-12-10€500kAJ Auxerre
2025-03-24€800kAJ Auxerre
2025-06-03€1MAJ Auxerre
2025-12-15€900kAJ Auxerre
2026-06-01€800kAJ Auxerre

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
−0.715

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 7% of the 423 Ligue 1 players.

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

Goalkeepers, all leagues485 players · median €1M

Valued above 39% of the 485 goalkeepers.

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

Where Léon 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).