FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
  • EnvironmentTerminalExplore, compare and track players; market, league and model views.
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Sven

Mijnans

AMNetherlands · AZ Alkmaar

№ 578804Elite €12.5M +0.18

Player dossierEredivisie

SvenMijnans

AMAttacking MidfieldMidfield

Club
AZ Alkmaar
League
Eredivisie
Nationality
Netherlands
Age
26
Height
190 cm
Foot
Left
Valued
28 May 2026

Reading the valuation

The market values Mijnans at €15M. Model A, which never saw Mijnans during training, estimates €12.5M: the market value is 20% above that estimate.

That is a factor of ×1.20. 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 €21.3M, 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.

▲ +0.18A €12.5M▼ −0.35B €21.3M
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
81
Minutes
6,398
Goals
26
Assists
15
Started
73/81
Min / app
79
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 Mijnans…

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 €15M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €15MModel A €12.5M

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

Sven Mijnans's percentiles among midfielders: Goals per 90 96th, Assists per 90 86th, Minutes, two years 96th, Starts 87th, Minutes, last 365 days 92nd, European club minutes 80th96thGoals86thAssists96thMinutes87thStarts92ndRecent80thEurope

Dashed ring: the midfielder median (50th percentile)

Minutes, two years

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

6,398 this player2,607 midfielder median96th percentile

451peer deciles · median line · this player ●9,624

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
€300k
Oct 2020
Peak
€15M
May 2026
Model target
€15M
May 2026
Valuations
16
1 club change
May 2026€15MAZ AlkmaarValuation the model is trained to reproduce

May 2026: €15M, AZ Alkmaar. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-10-14€300kSparta Rotterdam
2021-01-06€700kSparta Rotterdam
2021-05-19€700kSparta Rotterdam
2022-01-05€700kSparta Rotterdam
2022-06-08€850kSparta Rotterdam
2022-11-11€1MSparta Rotterdam
2023-03-17€3.5MAZ Alkmaar
2023-06-23€4MAZ Alkmaar
2023-10-17€6MAZ Alkmaar
2023-12-15€5MAZ Alkmaar
2024-05-31€6.5MAZ Alkmaar
2024-12-17€6.5MAZ Alkmaar
2025-05-28€9MAZ Alkmaar
2025-10-02€12MAZ Alkmaar
2025-12-02€14MAZ Alkmaar
2026-05-28€15MAZ 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
+0.183

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 95% of the 425 Eredivisie players.

€75k€500k€3M€20M€15MSee them in the Explorer →

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

Valued above 83% of the 1,687 midfielders.

€20k€200k€2M€20M€15MSee them in the Explorer →

Where Mijnans 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).