FairValue

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

Ndayishimiye

CBBurundi · OGC Nice

№ 674612Established €2.2M +1.16

Player dossierLigue 1

YoussoufNdayishimiye

CBCentre-BackDefender

Club
OGC Nice
League
Ligue 1
Nationality
Burundi
Age
27
Height
183 cm
Foot
Right
Valued
1 Jun 2026

Reading the valuation

The market values Ndayishimiye at €7M. Model A, which never saw Ndayishimiye during training, estimates €2.2M: the market value is 220% above that estimate.

That is a factor of ×3.20. 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 €1.5M, 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.

▲ +1.16A €2.2M▲ +1.53B €1.5M
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
30
Minutes
2,310
Goals
3
Assists
0
Started
27/30
Min / app
77
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 Ndayishimiye…

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 €7M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €7MModel 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

Youssouf Ndayishimiye's percentiles among defenders: Goals per 90 91st, Assists per 90 17th, Minutes, two years 40th, Starts 69th, Minutes, last 365 days 3rd, European club minutes 76th91stGoals17thAssists40thMinutes69thStarts3rdRecent76thEurope

Dashed ring: the defender median (50th percentile)

Goals per 90

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

0.12 this player0.03 defender median91st percentile

0.00peer deciles · median line · this player ●0.41

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
Jun 2019
Peak
€18M
Dec 2023
Model target
€7M
Jun 2026
Valuations
20
3 club changes
Jun 2026€7MOGC NiceValuation the model is trained to reproduce

Jun 2026: €7M, OGC Nice. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2019-06-18€50kAigle Noir FC de Makamba
2020-08-04€300kYeni Malatyaspor
2020-12-23€1.2MYeni Malatyaspor
2021-03-16€2MBasaksehir FK
2021-05-21€2MBasaksehir FK
2021-10-12€2.6MBasaksehir FK
2022-01-04€3.5MBasaksehir FK
2022-03-31€3.9MBasaksehir FK
2022-06-01€4MBasaksehir FK
2022-10-27€7MBasaksehir FK
2023-03-27€12MOGC Nice
2023-06-27€12MOGC Nice
2023-10-16€15MOGC Nice
2023-12-18€18MOGC Nice
2024-06-03€15MOGC Nice
2024-12-10€12MOGC Nice
2025-06-03€12MOGC Nice
2025-10-10€10MOGC Nice
2025-12-15€8MOGC Nice
2026-06-01€7MOGC Nice

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
+1.162

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 54% of the 423 Ligue 1 players.

€100k€750k€5M€30M€7MSee them in the Explorer →

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

Valued above 76% of the 2,065 defenders.

€20k€200k€2M€20M€7MSee them in the Explorer →

Where Ndayishimiye 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).