FairValue

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Jizz

Hornkamp

CFNetherlands · AZ Alkmaar

№ 185817Established €1.8M +0.32

Player dossierEredivisie

JizzHornkamp

CFCentre-ForwardAttack

Club
AZ Alkmaar
League
Eredivisie
Nationality
Netherlands
Age
28
Height
182 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Hornkamp at €2.5M. Model A, which never saw Hornkamp during training, estimates €1.8M: the market value is 38% above that estimate.

That is a factor of ×1.38. Model A's typical held-out miss is ×1.50 either way, so this gap is within its usual error.

Without league and club, Model B estimates €2.2M, 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.

▲ +0.32A €1.8M▲ +0.11B €2.2M
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
54
Minutes
3,289
Goals
19
Assists
4
Started
38/54
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 Hornkamp…

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 €2.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €2.5MModel A €1.8M

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

Jizz Hornkamp's percentiles among attackers: Goals per 90 90th, Assists per 90 36th, Minutes, two years 71st, Starts 69th, Minutes, last 365 days 56th, European club minutes 28th90thGoals36thAssists71stMinutes69thStarts56thRecent28thEurope

Dashed ring: the attacker median (50th percentile)

Goals per 90

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

0.52 this player0.26 attacker median90th 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
€150k
Oct 2018
Peak
€3M
Mar 2026
Model target
€2.5M
May 2026
Valuations
20
4 club changes
May 2026€2.5MAZ AlkmaarValuation the model is trained to reproduce

May 2026: €2.5M, AZ Alkmaar. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2018-10-04€150kSC Heerenveen
2018-12-28€300kSC Heerenveen
2019-06-12€600kSC Heerenveen
2019-10-28€400kFC Den Bosch
2020-04-08€350kFC Den Bosch
2020-06-29€350kFC Den Bosch
2020-10-24€400kFC Den Bosch
2020-12-31€375kFC Den Bosch
2021-10-12€425kFC Den Bosch
2022-01-12€400kFC Den Bosch
2022-06-08€650kWillem II Tilburg
2023-07-04€600kHeracles Almelo
2023-12-15€600kHeracles Almelo
2024-03-18€900kHeracles Almelo
2024-05-31€1MHeracles Almelo
2024-12-17€900kHeracles Almelo
2025-05-28€1.3MHeracles Almelo
2025-12-02€1.5MHeracles Almelo
2026-03-11€3MAZ Alkmaar
2026-05-28€2.5MAZ Alkmaar

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
+0.322

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 68% of the 425 Eredivisie players.

€75k€500k€3M€20M€2.5MSee them in the Explorer →

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

Valued above 48% of the 1,583 attackers.

€20k€300k€5M€75M€2.5MSee them in the Explorer →

Where Hornkamp 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).