FairValue

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Portrait of Eliezer Mayenda

Eliezer

Mayenda

CFSpain · Sunderland AFC

№ 967346Elite €17.8M −0.10

Image: FootyLogos

Player dossierPremier League

EliezerMayenda

CFCentre-ForwardAttack

Club
Sunderland AFC
League
Premier League
Nationality
Spain
Age
21
Height
183 cm
Foot
Left
Valued
3 Jun 2026

Reading the valuation

The market values Mayenda at €16M. Model A, which never saw Mayenda during training, estimates €17.8M: the market value is 10% below that estimate.

That is a factor of ×1.11. 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 €1.7M, 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.

▼ −0.10A €17.8M▲ +2.25B €1.7M
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
23
Minutes
943
Goals
2
Assists
1
Started
10/23
Min / app
41
Cards
0Y 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 Mayenda…

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 €16M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €16MModel A €17.8M

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

Eliezer Mayenda's percentiles among attackers: Goals per 90 33rd, Assists per 90 30th, Minutes, two years 17th, Starts 25th, Minutes, last 365 days 35th, European club minutes 28th33rdGoals30thAssists17thMinutes25thStarts35thRecent28thEurope

Dashed ring: the attacker median (50th percentile)

Minutes, last 365 days

Club minutes in the final year of the window: recent involvement, or the absence of it.

943 this player1,301 attacker median35th percentile

0peer deciles · median line · this player ●4,703

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
€200k
Oct 2022
Peak
€18M
Oct 2025
Model target
€16M
Jun 2026
Valuations
12
3 club changes
Jun 2026€16MSunderland AFCValuation the model is trained to reproduce

Jun 2026: €16M, Sunderland AFC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2022-10-28€200kFC Sochaux-Montbéliard
2023-06-16€300kFC Sochaux-Montbéliard
2023-10-27€500kSunderland AFC
2023-12-21€700kSunderland AFC
2024-05-30€700kHibernian FC
2024-09-24€1MSunderland AFC
2024-12-30€1MSunderland AFC
2025-03-28€4MSunderland AFC
2025-05-27€12MSunderland AFC
2025-10-17€18MSunderland AFC
2025-12-09€18MSunderland AFC
2026-06-03€16MSunderland AFC

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
−0.105

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 →

Premier League555 players · median €18M

Valued above 46% of the 555 Premier League players.

€150k€1M€7.5M€50M€16MSee them in the Explorer →

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

Valued above 84% of the 1,583 attackers.

€20k€300k€5M€75M€16MSee them in the Explorer →

Where Mayenda 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).