FairValue

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

Meijer

LBNetherlands · Club Brugge KV

№ 594227Established €4.1M −0.32

Player dossierPro League

BjornMeijer

LBLeft-BackDefender

Club
Club Brugge KV
League
Pro League
Nationality
Netherlands
Age
23
Height
190 cm
Foot
Left
Valued
4 Jun 2026

Reading the valuation

The market values Meijer at €3M. Model A, which never saw Meijer during training, estimates €4.1M: the market value is 27% below that estimate.

That is a factor of ×1.38. 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 €6.2M, 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.

▼ −0.32A €4.1M▼ −0.73B €6.2M
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
45
Minutes
1,623
Goals
1
Assists
5
Started
16/45
Min / app
36
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 Meijer…

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 €3M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €3MModel A €4.1M

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

Bjorn Meijer's percentiles among defenders: Goals per 90 67th, Assists per 90 99th, Minutes, two years 25th, Starts 2nd, Minutes, last 365 days 40th, European club minutes 87th67thGoals99thAssists25thMinutes2ndStarts40thRecent87thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.28 this player0.04 defender median99th 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
€250k
Jan 2022
Peak
€10M
Jun 2023
Model target
€3M
Jun 2026
Valuations
15
1 club change
Jun 2026€3MClub Brugge KVValuation the model is trained to reproduce

Jun 2026: €3M, Club Brugge KV. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2022-01-05€250kFC Groningen
2022-03-17€750kFC Groningen
2022-06-08€3MFC Groningen
2022-09-07€4.5MClub Brugge KV
2022-11-04€6.5MClub Brugge KV
2023-03-22€9MClub Brugge KV
2023-06-09€10MClub Brugge KV
2023-12-19€9MClub Brugge KV
2024-03-22€7MClub Brugge KV
2024-06-04€6MClub Brugge KV
2024-12-11€6MClub Brugge KV
2025-03-26€5MClub Brugge KV
2025-06-12€4MClub Brugge KV
2025-12-10€3.5MClub Brugge KV
2026-06-04€3MClub Brugge KV

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
−0.319

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 →

Pro League350 players · median €1.8M

Valued above 67% of the 350 Pro League players.

€100k€750k€5M€30M€3MSee them in the Explorer →

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

Valued above 59% of the 2,065 defenders.

€20k€200k€2M€20M€3MSee them in the Explorer →

Where Meijer 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).