FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Kang-in

Lee

AMKorea, South · Paris Saint-Germain

№ 557149Elite €25.8M +0.08

Player dossierLigue 1

Kang-inLee

AMAttacking MidfieldMidfield

Club
Paris Saint-Germain
League
Ligue 1
Nationality
Korea, South
Age
25
Height
174 cm
Foot
Left
Valued
1 Jun 2026

Reading the valuation

The market values Lee at €28M. Model A, which never saw Lee during training, estimates €25.8M: the market value is 8% above that estimate.

That is a factor of ×1.08. 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 €18.5M, 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.

▲ +0.08A €25.8M▲ +0.41B €18.5M
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
84
Minutes
4,065
Goals
11
Assists
11
Started
42/84
Min / app
48
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 Lee…

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 €28M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €28MModel A €25.8M

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 1,687 midfielders

Kang-in Lee's percentiles among midfielders: Goals per 90 88th, Assists per 90 91st, Minutes, two years 75th, Starts 21st, Minutes, last 365 days 61st, European club minutes 84th88thGoals91stAssists75thMinutes21stStarts61stRecent84thEurope

Dashed ring: the midfielder median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.24 this player0.09 midfielder median91st percentile

0.00peer deciles · median line · this player ●0.74

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
May 2018
Peak
€30M
Dec 2024
Model target
€28M
Jun 2026
Valuations
25
3 club changes
Jun 2026€28MParis Saint-GermainValuation the model is trained to reproduce

Jun 2026: €28M, Paris Saint-Germain. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2018-05-30€100kValencia Mestalla
2018-08-25€1MValencia Mestalla
2019-02-28€7.5MValencia CF
2019-06-11€10MValencia CF
2019-09-10€20MValencia CF
2019-12-20€20MValencia CF
2020-03-05€15MValencia CF
2020-04-08€13.5MValencia CF
2020-10-08€20MValencia CF
2021-01-05€15MValencia CF
2021-06-10€10MValencia CF
2021-12-30€10MRCD Mallorca
2022-03-21€8MRCD Mallorca
2022-06-03€6MRCD Mallorca
2022-09-23€9MRCD Mallorca
2022-11-07€12MRCD Mallorca
2023-03-23€15MRCD Mallorca
2023-06-13€22MRCD Mallorca
2023-12-18€22MParis Saint-Germain
2024-06-03€25MParis Saint-Germain
2024-12-10€30MParis Saint-Germain
2025-06-03€25MParis Saint-Germain
2025-12-15€25MParis Saint-Germain
2026-03-27€28MParis Saint-Germain
2026-06-01€28MParis Saint-Germain

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
+0.081

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 91% of the 423 Ligue 1 players.

€100k€750k€5M€30M€28MSee them in the Explorer →

Midfielders, all leagues1,687 players · median €2M

Valued above 93% of the 1,687 midfielders.

€20k€200k€2M€20M€28MSee them in the Explorer →

Where Lee 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).