FairValue

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Joris

Kramer

CBNetherlands · Go Ahead Eagles

№ 326329Emerging €2.3M −0.25

Player dossierEredivisie

JorisKramer

CBCentre-BackDefender

Club
Go Ahead Eagles
League
Eredivisie
Nationality
Netherlands
Age
29
Height
187 cm
Foot
Left
Valued
28 May 2026

Reading the valuation

The market values Kramer at €1.8M. Model A, which never saw Kramer during training, estimates €2.3M: the market value is 22% below that estimate.

That is a factor of ×1.28. 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 €7.7M, 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.

▼ −0.25A €2.3M▼ −1.45B €7.7M
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
87
Minutes
7,880
Goals
1
Assists
5
Started
87/87
Min / app
91
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 Kramer…

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 €1.8M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1.8MModel A €2.3M

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

Joris Kramer's percentiles among defenders: Goals per 90 36th, Assists per 90 62nd, Minutes, two years 99th, Starts 97th, Minutes, last 365 days 99th, European club minutes 73rd36thGoals62ndAssists99thMinutes97thStarts99thRecent73rdEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

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

7,880 this player2,860 defender median99th percentile

451peer deciles · median line · this player ●9,111

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
Apr 2015
Peak
€2M
May 2025
Model target
€1.8M
May 2026
Valuations
24
8 club changes
May 2026€1.8MGo Ahead EaglesValuation the model is trained to reproduce

May 2026: €1.8M, Go Ahead Eagles. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2015-04-06€50kAZ Alkmaar U19
2015-07-01€100kAZ Alkmaar U21
2017-02-02€125kFC Dordrecht
2017-06-21€125kFC Dordrecht
2018-03-01€150kAZ Alkmaar U21
2018-06-29€175kAZ Alkmaar U21
2019-01-21€200kAZ Alkmaar U21
2019-07-03€300kAZ Alkmaar
2019-12-18€300kAZ Alkmaar
2020-10-24€275kSC Cambuur Leeuwarden
2020-12-31€275kSC Cambuur Leeuwarden
2021-03-16€300kSC Cambuur Leeuwarden
2022-01-05€400kGo Ahead Eagles
2022-06-08€650kGo Ahead Eagles
2022-11-11€650kNEC Nijmegen
2023-06-23€650kNEC Nijmegen
2023-12-15€800kGo Ahead Eagles
2024-03-18€1MGo Ahead Eagles
2024-05-31€1.2MGo Ahead Eagles
2024-10-14€1.7MGo Ahead Eagles
2024-12-17€1.5MGo Ahead Eagles
2025-05-28€2MGo Ahead Eagles
2025-12-02€1.8MGo Ahead Eagles
2026-05-28€1.8MGo 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
−0.245

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 61% of the 425 Eredivisie players.

€75k€500k€3M€20M€1.8MSee them in the Explorer →

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

Valued above 48% of the 2,065 defenders.

€20k€200k€2M€20M€1.8MSee them in the Explorer →

Where Kramer 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).