FairValue

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Portrait of Ainsley Maitland-Niles

Ainsley

Maitland-Niles

RBEngland · Olympique Lyon

№ 285845Elite €18.9M −0.64

Image: FootyLogos

Player dossierLigue 1

AinsleyMaitland-Niles

RBRight-BackDefender

Club
Olympique Lyon
League
Ligue 1
Nationality
England
Age
28
Height
180 cm
Foot
Right
Valued
1 Jun 2026

Reading the valuation

The market values Maitland-Niles at €10M. Model A, which never saw Maitland-Niles during training, estimates €18.9M: the market value is 47% below that estimate.

That is a factor of ×1.89. 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 €22.5M, 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.

▼ −0.64A €18.9M▼ −0.81B €22.5M
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
81
Minutes
5,963
Goals
3
Assists
11
Started
64/81
Min / app
74
Cards
9Y 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 Maitland-Niles…

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 €10M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €10MModel A €18.9M

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

Ainsley Maitland-Niles's percentiles among defenders: Goals per 90 61st, Assists per 90 91st, Minutes, two years 92nd, Starts 43rd, Minutes, last 365 days 89th, European club minutes 91st61stGoals91stAssists92ndMinutes43rdStarts89thRecent91stEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

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

5,963 this player2,860 defender median92nd 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
€250k
Jun 2015
Peak
€18M
Sept 2019
Model target
€10M
Jun 2026
Valuations
26
8 club changes
Jun 2026€10MOlympique LyonValuation the model is trained to reproduce

Jun 2026: €10M, Olympique Lyon. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2015-06-05€250kArsenal FC U21
2015-09-24€250kIpswich Town
2016-04-20€750kIpswich Town
2017-10-23€1.5MArsenal FC
2018-01-02€5MArsenal FC
2018-05-28€7MArsenal FC
2018-12-19€7MArsenal FC
2019-06-13€12MArsenal FC
2019-09-12€18MArsenal FC
2019-12-10€18MArsenal FC
2020-04-08€14.5MArsenal FC
2020-10-13€18MArsenal FC
2021-03-18€18MWest Bromwich Albion
2021-06-08€16MArsenal FC
2021-12-23€12MArsenal FC
2022-06-07€10MAS Roma
2022-11-03€8MSouthampton FC
2023-06-20€8MArsenal FC
2023-10-16€6MOlympique Lyon
2023-12-18€5MOlympique Lyon
2024-03-19€7MOlympique Lyon
2024-06-03€9MOlympique Lyon
2024-12-10€10MOlympique Lyon
2025-06-03€12MOlympique Lyon
2025-12-15€10MOlympique Lyon
2026-06-01€10MOlympique Lyon

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
−0.637

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 →

Ligue 1423 players · median €5M

Valued above 66% of the 423 Ligue 1 players.

€100k€750k€5M€30M€10MSee them in the Explorer →

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

Valued above 81% of the 2,065 defenders.

€20k€200k€2M€20M€10MSee them in the Explorer →

Where Maitland-Niles 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).