FairValue

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Abdul

Mumin

CBGhana · Rayo Vallecano

№ 451801Established €2.4M +0.24

Player dossierLaLiga

AbdulMumin

CBCentre-BackDefender

Club
Rayo Vallecano
League
LaLiga
Nationality
Ghana
Age
28
Height
188 cm
Foot
Right
Valued
5 Jun 2026

Reading the valuation

The market values Mumin at €3M. Model A, which never saw Mumin during training, estimates €2.4M: the market value is 28% above that estimate.

That is a factor of ×1.28. 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 €2.6M, 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.

▲ +0.24A €2.4M▲ +0.16B €2.6M
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
28
Minutes
2,188
Goals
2
Assists
1
Started
26/28
Min / app
78
Cards
6Y 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 Mumin…

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 €2.4M

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

Abdul Mumin's percentiles among defenders: Goals per 90 81st, Assists per 90 51st, Minutes, two years 37th, Starts 78th, Minutes, last 365 days 3rd, European club minutes 30th81stGoals51stAssists37thMinutes78thStarts3rdRecent30thEurope

Dashed ring: the defender median (50th percentile)

Goals per 90

Club goals per 90 minutes played in the two years to the valuation date.

0.08 this player0.03 defender median81st percentile

0.00peer deciles · median line · this player ●0.41

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
€50k
Aug 2016
Peak
€5M
Dec 2024
Model target
€3M
Jun 2026
Valuations
23
5 club changes
Jun 2026€3MRayo VallecanoValuation the model is trained to reproduce

Jun 2026: €3M, Rayo Vallecano. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-08-12€50kFC Nordsjaelland U19
2016-12-12€100kFC Nordsjaelland U19
2017-06-21€100kFC Nordsjaelland U19
2017-12-18€100kFC Nordsjaelland
2018-06-07€200kHB Köge
2018-12-21€200kFC Nordsjaelland
2019-06-08€400kFC Nordsjaelland
2019-12-22€700kFC Nordsjaelland
2020-04-08€625kFC Nordsjaelland
2020-07-31€700kFC Nordsjaelland
2021-01-28€1.7MVitória Guimarães SC
2021-05-21€2MVitória Guimarães SC
2021-12-27€3MVitória Guimarães SC
2022-05-31€3MVitória Guimarães SC
2022-11-07€1.5MRayo Vallecano
2023-06-13€1.5MRayo Vallecano
2023-12-22€2MRayo Vallecano
2024-06-07€2.5MRayo Vallecano
2024-10-11€4MRayo Vallecano
2024-12-27€5MRayo Vallecano
2025-06-09€5MRayo Vallecano
2025-12-12€4MRayo Vallecano
2026-06-05€3MRayo Vallecano

Audit context group-level, not about this player

Audit group
non-UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
+0.244

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 →

LaLiga509 players · median €4M

Valued above 40% of the 509 LaLiga players.

€100k€1M€10M€100M€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 Mumin 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).