FairValue

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

Boogaard

DMNetherlands · AZ Alkmaar

№ 988406Established €1.4M +0.55

Player dossierEredivisie

KasperBoogaard

DMDefensive MidfieldMidfield

Club
AZ Alkmaar
League
Eredivisie
Nationality
Netherlands
Age
20
Height
187 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Boogaard at €2.5M. Model A, which never saw Boogaard during training, estimates €1.4M: the market value is 74% above that estimate.

That is a factor of ×1.74. 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 €1.2M, 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.

▲ +0.55A €1.4M▲ +0.75B €1.2M
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
13
Minutes
823
Goals
0
Assists
2
Started
9/13
Min / app
63
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 Boogaard…

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 €2.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €2.5MModel 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 1,687 midfielders

Kasper Boogaard's percentiles among midfielders: Goals per 90 10th, Assists per 90 88th, Minutes, two years 9th, Starts 50th, Minutes, last 365 days 25th, European club minutes 30th10thGoals88thAssists9thMinutes50thStarts25thRecent30thEurope

Dashed ring: the midfielder median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.22 this player0.09 midfielder median88th percentile

0.00peer deciles · median line · this player ●0.74

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
Dec 2024
Peak
€3M
Mar 2026
Model target
€2.5M
May 2026
Valuations
7
1 club change
May 2026€2.5MAZ AlkmaarValuation the model is trained to reproduce

May 2026: €2.5M, AZ Alkmaar. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2024-12-10€100kAZ Alkmaar U21
2025-03-14€200kAZ Alkmaar U21
2025-06-09€200kAZ Alkmaar U21
2025-10-16€350kAZ Alkmaar U21
2025-12-16€600kAZ Alkmaar U21
2026-03-11€3MAZ Alkmaar
2026-05-28€2.5MAZ Alkmaar

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
+0.554

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 68% of the 425 Eredivisie players.

€75k€500k€3M€20M€2.5MSee them in the Explorer →

Midfielders, all leagues1,687 players · median €2M

Valued above 51% of the 1,687 midfielders.

€20k€200k€2M€20M€2.5MSee them in the Explorer →

Where Boogaard 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).