FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Portrait of Jahmai Simpson-Pusey

Jahmai

Simpson-Pusey

CBEngland · 1.FC Köln

№ 942497Established €4.9M +0.61

Image: FootyLogos

Player dossierBundesliga

JahmaiSimpson-Pusey

CBCentre-BackDefender

Club
1.FC Köln
League
Bundesliga
Nationality
England
Age
20
Height
187 cm
Foot
Right
Valued
27 May 2026

Reading the valuation

The market values Simpson-Pusey at €9M. Model A, which never saw Simpson-Pusey during training, estimates €4.9M: the market value is 84% above that estimate.

That is a factor of ×1.84. 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 €2.7M, 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.

▲ +0.61A €4.9M▲ +1.21B €2.7M
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
17
Minutes
1,225
Goals
0
Assists
0
Started
14/17
Min / app
72
Cards
3Y 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 Simpson-Pusey…

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 €9M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €9MModel A €4.9M

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

Jahmai Simpson-Pusey's percentiles among defenders: Goals per 90 18th, Assists per 90 17th, Minutes, two years 16th, Starts 50th, Minutes, last 365 days 27th, European club minutes 71st18thGoals17thAssists16thMinutes50thStarts27thRecent71stEurope

Dashed ring: the defender median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

9% this player0% defender median71st percentile

0%peer deciles · median line · this player ●85%

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
€2M
Dec 2024
Peak
€9M
May 2026
Model target
€9M
May 2026
Valuations
5
2 club changes
May 2026€9M1.FC KölnValuation the model is trained to reproduce

May 2026: €9M, 1.FC Köln. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2024-12-16€2MManchester City U21
2025-05-30€5MManchester City U21
2025-12-10€4MCeltic FC
2026-03-20€6M1.FC Köln
2026-05-27€9M1.FC Köln

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
+0.608

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 →

Bundesliga451 players · median €5M

Valued above 64% of the 451 Bundesliga players.

€300k€2M€15M€100M€9MSee them in the Explorer →

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

Valued above 80% of the 2,065 defenders.

€20k€200k€2M€20M€9MSee them in the Explorer →

Where Simpson-Pusey 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).