FairValue

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

Yongwa

LBCameroon · FC Lorient

№ 717118Established €3M +0.52

Player dossierLigue 1

DarlinYongwa

LBLeft-BackDefender

Club
FC Lorient
League
Ligue 1
Nationality
Cameroon
Age
25
Height
177 cm
Foot
Left
Valued
1 Jun 2026

Reading the valuation

The market values Yongwa at €5M. Model A, which never saw Yongwa during training, estimates €3M: the market value is 68% above that estimate.

That is a factor of ×1.68. 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 €699k, 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.

▲ +0.52A €3M▲ +1.97B €699k
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
23
Minutes
1,305
Goals
0
Assists
1
Started
14/23
Min / app
57
Cards
4Y 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 Yongwa…

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 €5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €5MModel A €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

Darlin Yongwa's percentiles among defenders: Goals per 90 18th, Assists per 90 67th, Minutes, two years 19th, Starts 16th, Minutes, last 365 days 38th, European club minutes 30th18thGoals67thAssists19thMinutes16thStarts38thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.07 this player0.04 defender median67th percentile

0.00peer deciles · median line · this player ●0.58

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
€400k
Jan 2020
Peak
€6M
Mar 2026
Model target
€5M
Jun 2026
Valuations
18
1 club change
Jun 2026€5MFC LorientValuation the model is trained to reproduce

Jun 2026: €5M, FC Lorient. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-01-06€400kChamois Niortais FC
2020-04-08€350kChamois Niortais FC
2020-11-11€600kChamois Niortais FC
2021-03-11€1MChamois Niortais FC
2021-06-25€900kChamois Niortais FC
2021-12-27€1MChamois Niortais FC
2022-06-02€1.2MChamois Niortais FC
2022-11-02€1MFC Lorient
2023-06-27€1.2MFC Lorient
2023-12-18€1.5MFC Lorient
2024-06-03€1.5MFC Lorient
2024-12-04€2MFC Lorient
2025-03-12€3MFC Lorient
2025-06-02€4MFC Lorient
2025-10-10€3MFC Lorient
2025-12-15€4MFC Lorient
2026-03-27€6MFC Lorient
2026-06-01€5MFC Lorient

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
+0.520

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 45% of the 423 Ligue 1 players.

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

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

Valued above 70% of the 2,065 defenders.

€20k€200k€2M€20M€5MSee them in the Explorer →

Where Yongwa 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).