FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Portrait of Quilindschy Hartman

Quilindschy

Hartman

LBNetherlands · Burnley FC

№ 514285Elite €10.3M +0.44

Image: FootyLogos

Player dossierPremier League

QuilindschyHartman

LBLeft-BackDefender

Club
Burnley FC
League
Premier League
Nationality
Netherlands
Age
24
Height
183 cm
Foot
Left
Valued
3 Jun 2026

Reading the valuation

The market values Hartman at €16M. Model A, which never saw Hartman during training, estimates €10.3M: the market value is 55% above that estimate.

That is a factor of ×1.55. 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 €1.8M, 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.

▲ +0.44A €10.3M▲ +2.20B €1.8M
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
35
Minutes
2,654
Goals
0
Assists
6
Started
31/35
Min / app
76
Cards
1Y 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 Hartman…

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 €16M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €16MModel A €10.3M

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

Quilindschy Hartman's percentiles among defenders: Goals per 90 18th, Assists per 90 96th, Minutes, two years 46th, Starts 65th, Minutes, last 365 days 62nd, European club minutes 30th18thGoals96thAssists46thMinutes65thStarts62ndRecent30thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.20 this player0.04 defender median96th percentile

0.00peer deciles · median line · this player ●0.58

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
€400k
Sept 2022
Peak
€23M
Dec 2023
Model target
€16M
Jun 2026
Valuations
12
1 club change
Jun 2026€16MBurnley FCValuation the model is trained to reproduce

Jun 2026: €16M, Burnley FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2022-09-14€400kFeyenoord Rotterdam
2022-11-11€1MFeyenoord Rotterdam
2023-03-17€6.5MFeyenoord Rotterdam
2023-06-23€10MFeyenoord Rotterdam
2023-10-17€20MFeyenoord Rotterdam
2023-12-15€23MFeyenoord Rotterdam
2024-05-31€23MFeyenoord Rotterdam
2024-12-17€23MFeyenoord Rotterdam
2025-03-28€18MFeyenoord Rotterdam
2025-05-28€14MFeyenoord Rotterdam
2025-12-09€18MBurnley FC
2026-06-03€16MBurnley FC

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
+0.440

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 →

Premier League555 players · median €18M

Valued above 46% of the 555 Premier League players.

€150k€1M€7.5M€50M€16MSee them in the Explorer →

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

Valued above 88% of the 2,065 defenders.

€20k€200k€2M€20M€16MSee them in the Explorer →

Where Hartman 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).