FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Bert

Esselink

CBNetherlands · Dundee United FC

№ 462059Emerging €547k −0.45

Player dossierPremiership

BertEsselink

CBCentre-BackDefender

Club
Dundee United FC
League
Premiership
Nationality
Netherlands
Age
26
Height
191 cm
Foot
Right
Valued
20 May 2026

Reading the valuation

The market values Esselink at €350k. Model A, which never saw Esselink during training, estimates €547k: the market value is 36% below that estimate.

That is a factor of ×1.56. 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 €3.4M, 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.

▼ −0.45A €547k▼ −2.28B €3.4M
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
23
Minutes
1,914
Goals
1
Assists
0
Started
22/23
Min / app
83
Cards
4Y 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 Esselink…

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 €350k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €350kModel A €547k

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

Bert Esselink's percentiles among defenders: Goals per 90 62nd, Assists per 90 17th, Minutes, two years 32nd, Starts 86th, Minutes, last 365 days 58th, European club minutes 85th62ndGoals17thAssists32ndMinutes86thStarts58thRecent85thEurope

Dashed ring: the defender median (50th percentile)

Starts

Share of appearances started rather than entered from the bench.

96% this player83% defender median86th percentile

18%peer deciles · median line · this player ●100%

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
Sept 2021
Peak
€600k
Mar 2024
Model target
€350k
May 2026
Valuations
14
4 club changes
May 2026€350kDundee United FCValuation the model is trained to reproduce

May 2026: €350k, Dundee United FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2021-09-29€50kPAEEK Kyrenia
2022-01-11€250kAPOEL Nicosia
2022-06-20€300kAPOEL Nicosia
2023-01-10€300kOlympiakos Nicosia
2023-05-31€300kOlympiakos Nicosia
2023-10-06€450kStal Mielec
2023-12-29€500kStal Mielec
2024-03-28€600kStal Mielec
2024-06-07€500kStal Mielec
2024-12-09€400kStal Mielec
2025-04-03€300kStal Mielec
2025-05-28€300kStal Mielec
2025-12-10€350kDundee United FC
2026-05-20€350kDundee United 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
−0.446

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 →

Premiership311 players · median €400k

Valued above 45% of the 311 Premiership players.

€20k€150k€1M€7.5M€350kSee them in the Explorer →

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

Valued above 12% of the 2,065 defenders.

€20k€200k€2M€20M€350kSee them in the Explorer →

Where Esselink 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).