FairValue

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

Arrey-Mbi

CBGermany · SC Braga

№ 580193Established €12.1M −0.29

Player dossierLiga Portugal

BrightArrey-Mbi

CBCentre-BackDefender

Club
SC Braga
League
Liga Portugal
Nationality
Germany
Age
23
Height
187 cm
Foot
Left
Valued
28 May 2026

Reading the valuation

The market values Arrey-Mbi at €9M. Model A, which never saw Arrey-Mbi during training, estimates €12.1M: the market value is 25% below that estimate.

That is a factor of ×1.34. 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 €10.9M, closer to the market here, although it is usually further off (typical miss ×2.07).

A gap describes the model's arithmetic for this player's inputs, not what the player is worth.

▼ −0.29A €12.1M▼ −0.19B €10.9M
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
67
Minutes
5,253
Goals
0
Assists
0
Started
59/67
Min / app
78
Cards
8Y 1R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Arrey-Mbi…

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 €12.1M

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

Bright Arrey-Mbi's percentiles among defenders: Goals per 90 18th, Assists per 90 17th, Minutes, two years 86th, Starts 64th, Minutes, last 365 days 94th, European club minutes 98th18thGoals17thAssists86thMinutes64thStarts94thRecent98thEurope

Dashed ring: the defender median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

38% this player0% defender median98th 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
€500k
Sept 2020
Peak
€9M
May 2026
Model target
€9M
May 2026
Valuations
16
3 club changes
May 2026€9MSC BragaValuation the model is trained to reproduce

May 2026: €9M, SC Braga. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-09-11€500kFC Bayern Munich II
2021-01-20€1MFC Bayern Munich II
2021-06-14€1MFC Bayern Munich II
2021-12-15€1.3MFC Bayern Munich II
2022-06-09€1.3M1.FC Köln
2022-09-28€800kHannover 96
2022-11-30€1MHannover 96
2023-06-28€800kHannover 96
2023-10-20€1.5MHannover 96
2023-12-15€2.5MHannover 96
2024-06-06€2.5MHannover 96
2024-10-08€6MSC Braga
2024-12-19€6MSC Braga
2025-05-30€6MSC Braga
2025-12-18€7MSC Braga
2026-05-28€9MSC Braga

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
−0.294

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 →

Liga Portugal423 players · median €1M

Valued above 86% of the 423 Liga Portugal players.

€20k€200k€2M€20M€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 Arrey-Mbi 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).