FairValue

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Jasper

Dahlhaus

LBNetherlands · Fortuna Sittard

№ 576682Emerging €1.4M +0.03

Player dossierEredivisie

JasperDahlhaus

LBLeft-BackDefender

Club
Fortuna Sittard
League
Eredivisie
Nationality
Netherlands
Age
24
Height
176 cm
Foot
Left
Valued
28 May 2026

Reading the valuation

The market values Dahlhaus at €1.4M. Model A, which never saw Dahlhaus during training, estimates €1.4M: the market value is 3% above that estimate.

That is a factor of ×1.03. 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 €2.6M, 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.

▲ +0.03A €1.4M▼ −0.63B €2.6M
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
60
Minutes
4,018
Goals
2
Assists
3
Started
45/60
Min / app
67
Cards
9Y 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 Dahlhaus…

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 €1.4M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1.4MModel A €1.4M

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 2,065 defenders

Jasper Dahlhaus's percentiles among defenders: Goals per 90 60th, Assists per 90 66th, Minutes, two years 70th, Starts 35th, Minutes, last 365 days 68th, European club minutes 30th60thGoals66thAssists70thMinutes35thStarts68thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

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

4,018 this player2,860 defender median70th 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
€100k
Oct 2020
Peak
€1.4M
May 2026
Model target
€1.4M
May 2026
Valuations
14
2 club changes
May 2026€1.4MFortuna SittardValuation the model is trained to reproduce

May 2026: €1.4M, Fortuna Sittard. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-10-14€100kWillem II Tilburg U21
2021-10-12€175kFC Eindhoven
2022-01-12€175kFC Eindhoven
2022-03-24€300kFC Eindhoven
2022-06-23€400kFC Eindhoven
2023-04-03€500kFC Eindhoven
2023-07-04€500kFC Eindhoven
2024-01-08€500kFC Eindhoven
2024-06-10€450kFC Eindhoven
2024-12-17€550kFortuna Sittard
2025-03-28€700kFortuna Sittard
2025-05-28€1MFortuna Sittard
2025-12-02€1.3MFortuna Sittard
2026-05-28€1.4MFortuna Sittard

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
+0.032

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 54% of the 425 Eredivisie players.

€75k€500k€3M€20M€1.4MSee them in the Explorer →

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

Valued above 42% of the 2,065 defenders.

€20k€200k€2M€20M€1.4MSee them in the Explorer →

Where Dahlhaus 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).