FairValue

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

Faberski

RWPoland · PEC Zwolle

№ 949480Emerging €335k +0.40

Player dossierEredivisie

JanFaberski

RWRight WingerAttack

Club
PEC Zwolle
League
Eredivisie
Nationality
Poland
Age
20
Height
176 cm
Foot
Left
Valued
28 May 2026

Reading the valuation

The market values Faberski at €500k. Model A, which never saw Faberski during training, estimates €335k: the market value is 49% above that estimate.

That is a factor of ×1.49. 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 €833k, 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.

▲ +0.40A €335k▼ −0.51B €833k
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
19
Minutes
546
Goals
0
Assists
2
Started
5/19
Min / app
29
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 Faberski…

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 €500k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €500kModel A €335k

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 1,583 attackers

Jan Faberski's percentiles among attackers: Goals per 90 3rd, Assists per 90 93rd, Minutes, two years 3rd, Starts 8th, Minutes, last 365 days 17th, European club minutes 28th3rdGoals93rdAssists3rdMinutes8thStarts17thRecent28thEurope

Dashed ring: the attacker median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.33 this player0.15 attacker median93rd percentile

0.00peer deciles · median line · this player ●0.73

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
€25k
Jun 2022
Peak
€800k
Sept 2024
Model target
€500k
May 2026
Valuations
6
2 club changes
May 2026€500kPEC ZwolleValuation the model is trained to reproduce

May 2026: €500k, PEC Zwolle. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2022-06-14€25kJagiellonia Bialystok
2024-09-29€800kAjax Amsterdam U21
2024-12-10€800kAjax Amsterdam U21
2025-06-09€700kAjax Amsterdam U21
2025-12-02€700kPEC Zwolle
2026-05-28€500kPEC Zwolle

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
+0.401

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 25% of the 425 Eredivisie players.

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

Attackers, all leagues1,583 players · median €2.5M

Valued above 15% of the 1,583 attackers.

€20k€300k€5M€75M€500kSee them in the Explorer →

Where Faberski 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).