FairValue

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Portrait of Jari De Busser

Jari De

Busser

GKBelgium · Go Ahead Eagles

№ 426849Established €2.4M +0.51

Image: FootyLogos

Player dossierEredivisie

Jari DeBusser

GKGoalkeeperGoalkeeper

Club
Go Ahead Eagles
League
Eredivisie
Nationality
Belgium
Age
26
Height
190 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Busser at €4M. Model A, which never saw Busser during training, estimates €2.4M: the market value is 67% above that estimate.

That is a factor of ×1.67. 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 €7.4M, 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 €2.4M▼ −0.61B €7.4M
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
65
Minutes
5,970
Started
65/65
Min / app
92
Cards
2Y 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 Busser…

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 €4M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €4MModel A €2.4M

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

Jari De Busser's percentiles among goalkeepers: Minutes, two years 85th, Starts 62nd, Minutes, last 365 days 97th, European club minutes 76th85thMinutes62ndStarts97thRecent76thEurope

Dashed ring: the goalkeeper median (50th percentile)

Minutes, last 365 days

Club minutes in the final year of the window: recent involvement, or the absence of it.

4,200 this player1,560 goalkeeper median97th percentile

0peer deciles · median line · this player ●4,970

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
Aug 2016
Peak
€4M
May 2026
Model target
€4M
May 2026
Valuations
24
4 club changes
May 2026€4MGo Ahead EaglesValuation the model is trained to reproduce

May 2026: €4M, Go Ahead Eagles. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-08-03€50kLierse SK U21
2017-01-21€50kLierse SK U21
2017-06-06€50kLierse SK U21
2017-10-25€150kLierse SK (-2018)
2018-12-27€150kKAA Gent
2019-06-10€150kKAA Gent
2019-12-13€150kKAA Gent
2020-07-29€200kKAA Gent
2020-10-21€100kLommel SK
2021-02-23€50kLommel SK
2021-10-13€50kLommel SK
2022-01-13€50kLommel SK
2022-04-19€250kLommel SK
2022-12-22€250kLommel SK
2023-05-30€300kLommel SK
2023-10-02€400kLommel SK
2023-12-28€400kLommel SK
2024-06-20€500kLommel SK
2024-12-17€400kGo Ahead Eagles
2025-03-28€1MGo Ahead Eagles
2025-05-28€2MGo Ahead Eagles
2025-10-02€3MGo Ahead Eagles
2025-12-02€3MGo Ahead Eagles
2026-05-28€4MGo Ahead Eagles

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
+0.515

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 →

Eredivisie425 players · median €1M

Valued above 76% of the 425 Eredivisie players.

€75k€500k€3M€20M€4MSee them in the Explorer →

Goalkeepers, all leagues485 players · median €1M

Valued above 75% of the 485 goalkeepers.

€20k€200k€2M€20M€4MSee them in the Explorer →

Where Busser 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).