FairValue

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Mickaël

Biron

CFMartinique · 1.FC Nuremberg

№ 524860Emerging €1.7M −0.89

Player dossierBundesliga

MickaëlBiron

CFCentre-ForwardAttack

Club
1.FC Nuremberg
League
Bundesliga
Nationality
Martinique
Age
28
Height
170 cm
Foot
Right
Valued
16 Dec 2025

Reading the valuation

The market values Biron at €700k. Model A, which never saw Biron during training, estimates €1.7M: the market value is 59% below that estimate.

That is a factor of ×2.43. 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 €548k, 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.

▼ −0.89A €1.7M▲ +0.25B €548k
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
20
Minutes
761
Goals
4
Assists
1
Started
8/20
Min / app
38
Cards
1Y 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 Biron…

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 €700k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €700kModel A €1.7M

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 1,583 attackers

Mickaël Biron's percentiles among attackers: Goals per 90 85th, Assists per 90 39th, Minutes, two years 11th, Starts 21st, Minutes, last 365 days 1st, European club minutes 28th85thGoals39thAssists11thMinutes21stStarts1stRecent28thEurope

Dashed ring: the attacker median (50th percentile)

Goals per 90

Club goals per 90 minutes played in the two years to the valuation date.

0.47 this player0.26 attacker median85th percentile

0.00peer deciles · median line · this player ●1.17

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
€100k
Aug 2020
Peak
€3.5M
Mar 2024
Model target
€700k
Dec 2025
Valuations
17
4 club changes
Dec 2025€700k1.FC NurembergValuation the model is trained to reproduce

Dec 2025: €700k, 1.FC Nuremberg. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-08-14€100kAS Nancy-Lorraine
2020-11-11€600kAS Nancy-Lorraine
2021-03-11€1MAS Nancy-Lorraine
2021-06-25€1.3MAS Nancy-Lorraine
2021-10-27€1.1MAS Nancy-Lorraine
2021-12-27€1MAS Nancy-Lorraine
2022-06-02€900kAS Nancy-Lorraine
2022-12-22€800kRWD Molenbeek
2023-05-30€1.2MRWD Molenbeek
2023-10-23€2MRWD Molenbeek
2023-12-19€2MRWD Molenbeek
2024-03-22€3.5MRWD Molenbeek
2024-06-04€2.5MRWD Molenbeek
2024-10-02€2MOud-Heverlee Leuven
2024-12-11€1.5MOud-Heverlee Leuven
2025-04-24€1.2MRWD Molenbeek
2025-12-16€700k1.FC Nuremberg

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
−0.887

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 →

Bundesliga451 players · median €5M

Valued above 3% of the 451 Bundesliga players.

€300k€2M€15M€100M€700kSee them in the Explorer →

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

Valued above 22% of the 1,583 attackers.

€20k€300k€5M€75M€700kSee them in the Explorer →

Where Biron 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).