FairValue

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

Lefort

CBMauritania · Angers SCO

№ 192492Emerging €2.2M −0.79

Player dossierLigue 1

JordanLefort

CBCentre-BackDefender

Club
Angers SCO
League
Ligue 1
Nationality
Mauritania
Age
32
Height
184 cm
Foot
Left
Valued
1 Jun 2026

Reading the valuation

The market values Lefort at €1M. Model A, which never saw Lefort during training, estimates €2.2M: the market value is 55% below that estimate.

That is a factor of ×2.20. 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 €2M, 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.

▼ −0.79A €2.2M▼ −0.70B €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
68
Minutes
6,120
Goals
0
Assists
3
Started
68/68
Min / app
90
Cards
5Y 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 Lefort…

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 €1M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1MModel A €2.2M

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

Jordan Lefort's percentiles among defenders: Goals per 90 18th, Assists per 90 53rd, Minutes, two years 93rd, Starts 97th, Minutes, last 365 days 90th, European club minutes 30th18thGoals53rdAssists93rdMinutes97thStarts90thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Starts

Share of appearances started rather than entered from the bench.

100% this player83% defender median97th percentile

18%peer deciles · median line · this player ●100%

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
Jul 2016
Peak
€3M
Jun 2019
Model target
€1M
Jun 2026
Valuations
21
5 club changes
Jun 2026€1MAngers SCOValuation the model is trained to reproduce

Jun 2026: €1M, Angers SCO. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-07-13€150kAmiens SC
2017-03-20€400kAmiens SC
2017-06-15€700kAmiens SC
2018-05-16€700kQuevilly Rouen Métropole
2018-12-17€700kAmiens SC
2019-06-03€3MAmiens SC
2019-12-19€2MAmiens SC
2020-04-08€1.6MBSC Young Boys
2020-07-31€1.6MBSC Young Boys
2020-12-28€1.6MBSC Young Boys
2021-06-23€1.7MBSC Young Boys
2022-01-03€1MBSC Young Boys
2022-06-08€1MBSC Young Boys
2022-10-28€900kParis FC
2023-06-16€900kParis FC
2023-12-13€900kAngers SCO
2024-06-11€1MAngers SCO
2024-12-10€1.2MAngers SCO
2025-06-03€1.5MAngers SCO
2025-12-15€1.2MAngers SCO
2026-06-01€1MAngers SCO

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
−0.790

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 10% of the 423 Ligue 1 players.

€100k€750k€5M€30M€1MSee them in the Explorer →

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

Valued above 35% of the 2,065 defenders.

€20k€200k€2M€20M€1MSee them in the Explorer →

Where Lefort 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).