FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Portrait of Pierre Kalulu

Pierre

Kalulu

CBFrance · Juventus FC

№ 585949World Class €31.9M 0.00

Close-up

Image: FootyLogos

Player dossierSerie A

PierreKalulu

CBCentre-BackDefender

Club
Juventus FC
League
Serie A
Nationality
France
Age
25
Height
182 cm
Foot
Right
Valued
29 May 2026

Reading the valuation

The market values Kalulu at €32M. Model A, which never saw Kalulu during training, estimates €31.9M: the market value is level with that estimate.

That is a factor of ×1.00. 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 €31.3M, 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.

▲ 0.00A €31.9M▲ +0.02B €31.3M
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
92
Minutes
7,902
Goals
3
Assists
8
Started
88/92
Min / app
86
Cards
6Y 1R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Kalulu…

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 €32M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €32MModel A €31.9M

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

Pierre Kalulu's percentiles among defenders: Goals per 90 52nd, Assists per 90 75th, Minutes, two years 99th, Starts 86th, Minutes, last 365 days 100th, European club minutes 90th52ndGoals75thAssists99thMinutes86thStarts100thRecent90thEurope

Dashed ring: the defender median (50th percentile)

Minutes, last 365 days

Club minutes in the final year of the window: recent involvement, or the absence of it.

4,741 this player1,687 defender median100th percentile

0peer deciles · median line · this player ●4,941

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
€500k
Oct 2020
Peak
€35M
Nov 2022
Model target
€32M
May 2026
Valuations
17
1 club change
May 2026€32MJuventus FCValuation the model is trained to reproduce

May 2026: €32M, Juventus FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-10-29€500kAC Milan
2020-12-29€2MAC Milan
2021-03-23€7MAC Milan
2021-06-03€7MAC Milan
2021-12-28€10MAC Milan
2022-03-15€17MAC Milan
2022-06-07€28MAC Milan
2022-11-11€35MAC Milan
2023-06-15€30MAC Milan
2023-10-11€25MAC Milan
2023-12-20€25MAC Milan
2024-06-05€20MAC Milan
2024-12-18€26MJuventus FC
2025-06-17€28MJuventus FC
2025-12-23€28MJuventus FC
2026-03-24€32MJuventus FC
2026-05-29€32MJuventus 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
+0.004

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 →

Serie A507 players · median €5.5M

Valued above 94% of the 507 Serie A players.

€100k€750k€5M€30M€32MSee them in the Explorer →

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

Valued above 96% of the 2,065 defenders.

€20k€200k€2M€20M€32MSee them in the Explorer →

Where Kalulu 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).