FairValue

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Sam

Kersten

CBNetherlands · SC Heerenveen

№ 430797Established €2.2M −0.08

Player dossierEredivisie

SamKersten

CBCentre-BackDefender

Club
SC Heerenveen
League
Eredivisie
Nationality
Netherlands
Age
28
Height
191 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Kersten at €2M. Model A, which never saw Kersten during training, estimates €2.2M: the market value is 8% below that estimate.

That is a factor of ×1.08. 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 €4.1M, 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.

▼ −0.08A €2.2M▼ −0.71B €4.1M
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
67
Minutes
5,258
Goals
2
Assists
1
Started
61/67
Min / app
78
Cards
7Y 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 Kersten…

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 €2.2M

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

Sam Kersten's percentiles among defenders: Goals per 90 52nd, Assists per 90 36th, Minutes, two years 86th, Starts 72nd, Minutes, last 365 days 81st, European club minutes 30th52ndGoals36thAssists86thMinutes72ndStarts81stRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

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

5,258 this player2,860 defender median86th 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
€25k
Dec 2016
Peak
€2M
May 2026
Model target
€2M
May 2026
Valuations
20
2 club changes
May 2026€2MSC HeerenveenValuation the model is trained to reproduce

May 2026: €2M, SC Heerenveen. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-12-02€25kFC Den Bosch
2017-06-21€50kFC Den Bosch
2018-03-01€125kFC Den Bosch
2018-06-29€200kFC Den Bosch
2019-01-21€300kFC Den Bosch
2019-07-03€500kFC Den Bosch
2019-12-18€500kPEC Zwolle
2020-04-08€450kPEC Zwolle
2020-10-14€800kPEC Zwolle
2021-05-19€800kPEC Zwolle
2022-01-05€650kPEC Zwolle
2022-06-08€650kPEC Zwolle
2023-07-04€500kPEC Zwolle
2023-12-15€700kPEC Zwolle
2024-03-18€800kPEC Zwolle
2024-05-31€800kPEC Zwolle
2024-12-17€800kSC Heerenveen
2025-05-28€1MSC Heerenveen
2025-12-02€1.5MSC Heerenveen
2026-05-28€2MSC Heerenveen

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
−0.079

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 62% of the 425 Eredivisie players.

€75k€500k€3M€20M€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 Kersten 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).