FairValue

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Jean-Kévin

Duverne

CBHaiti · KAA Gent

№ 344864Established €1.2M +0.51

Player dossierPro League

Jean-KévinDuverne

CBCentre-BackDefender

Club
KAA Gent
League
Pro League
Nationality
Haiti
Age
28
Height
184 cm
Foot
Right
Valued
4 Jun 2026

Reading the valuation

The market values Duverne at €2M. Model A, which never saw Duverne during training, estimates €1.2M: the market value is 66% above that estimate.

That is a factor of ×1.66. 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 €1.1M, 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.

▲ +0.51A €1.2M▲ +0.59B €1.1M
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
38
Minutes
2,324
Goals
4
Assists
1
Started
26/38
Min / app
61
Cards
8Y 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 Duverne…

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 €2M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €2MModel A €1.2M

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

Jean-Kévin Duverne's percentiles among defenders: Goals per 90 96th, Assists per 90 49th, Minutes, two years 40th, Starts 25th, Minutes, last 365 days 33rd, European club minutes 30th96thGoals49thAssists40thMinutes25thStarts33rdRecent30thEurope

Dashed ring: the defender median (50th percentile)

Goals per 90

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

0.15 this player0.03 defender median96th percentile

0.00peer deciles · median line · this player ●0.41

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
€150k
Sept 2015
Peak
€4M
Jan 2021
Model target
€2M
Jun 2026
Valuations
23
5 club changes
Jun 2026€2MKAA GentValuation the model is trained to reproduce

Jun 2026: €2M, KAA Gent. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2015-09-06€150kRC Lens B
2017-03-20€1.8MRC Lens
2017-06-15€1.8MRC Lens
2018-05-16€2.5MRC Lens
2019-01-08€2MRC Lens
2019-06-27€2MRC Lens
2019-12-19€2MStade Brestois 29
2020-04-08€1.6MStade Brestois 29
2020-10-15€2MStade Brestois 29
2021-01-07€4MStade Brestois 29
2021-06-04€3.5MStade Brestois 29
2021-12-16€3.2MStade Brestois 29
2022-03-23€3.5MStade Brestois 29
2022-05-30€4MStade Brestois 29
2022-11-02€4MStade Brestois 29
2023-06-27€4MStade Brestois 29
2023-12-18€3.5MFC Nantes
2024-06-03€3.5MFC Nantes
2024-12-10€3MFC Nantes
2025-06-12€2.5MKV Kortrijk
2025-12-10€2.5MKAA Gent
2026-03-13€2MKAA Gent
2026-06-04€2MKAA Gent

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
+0.510

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 →

Pro League350 players · median €1.8M

Valued above 50% of the 350 Pro League players.

€100k€750k€5M€30M€2MSee them in the Explorer →

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

Valued above 49% of the 2,065 defenders.

€20k€200k€2M€20M€2MSee them in the Explorer →

Where Duverne 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).