FairValue

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Portrait of Ola Aina

Ola

Aina

RBNigeria · Nottingham Forest

№ 236490Elite €12.7M +0.35

Image: FootyLogos

Player dossierPremier League

OlaAina

RBRight-BackDefender

Club
Nottingham Forest
League
Premier League
Nationality
Nigeria
Age
29
Height
184 cm
Foot
Right
Valued
3 Jun 2026

Reading the valuation

The market values Aina at €18M. Model A, which never saw Aina during training, estimates €12.7M: the market value is 42% above that estimate.

That is a factor of ×1.42. 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 €2.2M, 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.

▲ +0.35A €12.7M▲ +2.09B €2.2M
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
63
Minutes
5,352
Goals
2
Assists
2
Started
60/63
Min / app
85
Cards
8Y 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 Aina…

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 €18M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €18MModel A €12.7M

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

Ola Aina's percentiles among defenders: Goals per 90 52nd, Assists per 90 47th, Minutes, two years 87th, Starts 85th, Minutes, last 365 days 65th, European club minutes 72nd52ndGoals47thAssists87thMinutes85thStarts65thRecent72ndEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

Total club minutes in the two-year window: how much the player was used.

5,352 this player2,860 defender median87th percentile

451peer deciles · median line · this player ●9,111

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
Aug 2016
Peak
€22M
May 2025
Model target
€18M
Jun 2026
Valuations
28
6 club changes
Jun 2026€18MNottingham ForestValuation the model is trained to reproduce

Jun 2026: €18M, Nottingham Forest. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-08-01€500kChelsea FC
2017-02-20€1MChelsea FC
2017-06-28€1MChelsea FC
2017-09-18€1.5MHull City
2018-07-01€4MChelsea FC
2018-12-20€6.5MTorino FC
2019-03-01€8.5MTorino FC
2019-06-06€10MTorino FC
2019-12-12€10MTorino FC
2020-04-08€8MTorino FC
2020-08-25€7MTorino FC
2020-10-13€7MFulham FC
2021-03-18€7MFulham FC
2021-06-08€6MFulham FC
2021-12-28€5.5MTorino FC
2022-03-15€4MTorino FC
2022-06-07€3.5MTorino FC
2022-11-11€3.5MTorino FC
2023-06-15€3.5MTorino FC
2023-10-09€5MNottingham Forest
2023-12-19€8MNottingham Forest
2024-03-14€10MNottingham Forest
2024-05-27€12MNottingham Forest
2024-12-16€14MNottingham Forest
2025-03-18€20MNottingham Forest
2025-05-30€22MNottingham Forest
2025-12-09€20MNottingham Forest
2026-06-03€18MNottingham Forest

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
+0.352

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 50% of the 555 Premier League players.

€150k€1M€7.5M€50M€18MSee them in the Explorer →

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

Valued above 89% of the 2,065 defenders.

€20k€200k€2M€20M€18MSee them in the Explorer →

Where Aina 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).