FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Portrait of Leandro Trossard

Leandro

Trossard

LWBelgium · Arsenal FC

№ 144028Elite €14.1M +0.24

Image: FootyLogos

Player dossierPremier League

LeandroTrossard

LWLeft WingerAttack

Club
Arsenal FC
League
Premier League
Nationality
Belgium
Age
31
Height
172 cm
Foot
Right
Valued
3 Jun 2026

Reading the valuation

The market values Trossard at €18M. Model A, which never saw Trossard during training, estimates €14.1M: the market value is 28% above that estimate.

That is a factor of ×1.28. 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 €6.7M, 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.

▲ +0.24A €14.1M▲ +0.98B €6.7M
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
102
Minutes
6,083
Goals
18
Assists
20
Started
65/102
Min / app
60
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 Trossard…

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 €14.1M

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

Leandro Trossard's percentiles among attackers: Goals per 90 51st, Assists per 90 89th, Minutes, two years 97th, Starts 58th, Minutes, last 365 days 93rd, European club minutes 84th51stGoals89thAssists97thMinutes58thStarts93rdRecent84thEurope

Dashed ring: the attacker median (50th percentile)

Minutes, two years

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

6,083 this player2,242 attacker median97th percentile

450peer deciles · median line · this player ●8,788

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
€50k
Jan 2012
Peak
€38M
Dec 2023
Model target
€18M
Jun 2026
Valuations
33
6 club changes
Jun 2026€18MArsenal FCValuation the model is trained to reproduce

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

Show as a table
DateMarket valueClub
2012-01-05€50kKRC Genk U19
2012-06-17€100kKRC Genk U19
2013-01-09€200kKRC Genk
2014-10-09€200kLommel United
2015-02-03€400kLommel United
2015-05-16€500kLommel United
2015-10-22€700kOud-Heverlee Leuven
2016-02-07€1.5MOud-Heverlee Leuven
2016-04-14€2MOud-Heverlee Leuven
2016-07-15€2MKRC Genk
2017-01-21€2.5MKRC Genk
2017-06-06€4MKRC Genk
2018-01-09€4MKRC Genk
2018-06-03€7MKRC Genk
2018-09-11€10MKRC Genk
2018-12-27€14MKRC Genk
2019-06-10€16MKRC Genk
2019-12-10€16MBrighton & Hove Albion
2020-04-08€13MBrighton & Hove Albion
2020-10-13€15MBrighton & Hove Albion
2021-03-18€15MBrighton & Hove Albion
2021-05-26€17MBrighton & Hove Albion
2021-12-23€17MBrighton & Hove Albion
2022-06-15€20MBrighton & Hove Albion
2022-09-15€25MBrighton & Hove Albion
2022-11-03€30MBrighton & Hove Albion
2023-06-20€35MArsenal FC
2023-12-19€38MArsenal FC
2024-05-27€35MArsenal FC
2024-12-16€30MArsenal FC
2025-05-30€22MArsenal FC
2025-12-09€20MArsenal FC
2026-06-03€18MArsenal FC

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
+0.245

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 →

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

Valued above 85% of the 1,583 attackers.

€20k€300k€5M€75M€18MSee them in the Explorer →

Where Trossard 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).