FairValue

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

Niakhaté

CBSenegal · Olympique Lyon

№ 291200Elite €11.3M +0.28

Player dossierLigue 1

MoussaNiakhaté

CBCentre-BackDefender

Club
Olympique Lyon
League
Ligue 1
Nationality
Senegal
Age
30
Height
190 cm
Foot
Left
Valued
1 Jun 2026

Reading the valuation

The market values Niakhaté at €15M. Model A, which never saw Niakhaté during training, estimates €11.3M: the market value is 33% above that estimate.

That is a factor of ×1.33. 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 €12.7M, 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.

▲ +0.28A €11.3M▲ +0.17B €12.7M
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
81
Minutes
6,974
Goals
1
Assists
2
Started
77/81
Min / app
86
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 Niakhaté…

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 €15M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €15MModel A €11.3M

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

Moussa Niakhaté's percentiles among defenders: Goals per 90 36th, Assists per 90 41st, Minutes, two years 98th, Starts 84th, Minutes, last 365 days 96th, European club minutes 86th36thGoals41stAssists98thMinutes84thStarts96thRecent86thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

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

6,974 this player2,860 defender median98th 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
€150k
Apr 2015
Peak
€18M
Dec 2021
Model target
€15M
Jun 2026
Valuations
29
4 club changes
Jun 2026€15MOlympique LyonValuation the model is trained to reproduce

Jun 2026: €15M, Olympique Lyon. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2015-04-05€150kValenciennes FC
2015-06-06€300kValenciennes FC
2016-02-04€300kValenciennes FC
2016-07-13€300kValenciennes FC
2017-03-20€400kValenciennes FC
2017-06-15€400kValenciennes FC
2018-01-24€3MFC Metz
2018-06-04€5MFC Metz
2018-08-22€6M1.FSV Mainz 05
2018-12-18€10M1.FSV Mainz 05
2019-06-05€14M1.FSV Mainz 05
2019-12-17€14M1.FSV Mainz 05
2020-04-08€11M1.FSV Mainz 05
2020-11-26€9M1.FSV Mainz 05
2021-02-10€7.5M1.FSV Mainz 05
2021-03-31€10M1.FSV Mainz 05
2021-06-09€15M1.FSV Mainz 05
2021-12-22€18M1.FSV Mainz 05
2022-06-09€18M1.FSV Mainz 05
2022-11-03€18MNottingham Forest
2023-06-20€18MNottingham Forest
2023-12-19€16MNottingham Forest
2024-05-27€16MNottingham Forest
2024-10-07€15MOlympique Lyon
2024-12-10€15MOlympique Lyon
2025-06-03€15MOlympique Lyon
2025-12-15€15MOlympique Lyon
2026-03-27€18MOlympique Lyon
2026-06-01€15MOlympique Lyon

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
+0.283

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 76% of the 423 Ligue 1 players.

€100k€750k€5M€30M€15MSee them in the Explorer →

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

Valued above 87% of the 2,065 defenders.

€20k€200k€2M€20M€15MSee them in the Explorer →

Where Niakhaté 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).