FairValue

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Woo-yeong

Jeong

AMKorea, South · 1.FC Union Berlin

№ 297583Established €4.7M −0.29

Player dossierBundesliga

Woo-yeongJeong

AMAttacking MidfieldMidfield

Club
1.FC Union Berlin
League
Bundesliga
Nationality
Korea, South
Age
26
Height
179 cm
Foot
Right
Valued
27 May 2026

Reading the valuation

The market values Jeong at €3.5M. Model A, which never saw Jeong during training, estimates €4.7M: the market value is 25% below that estimate.

That is a factor of ×1.34. 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 €1.2M, 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.

▼ −0.29A €4.7M▲ +1.03B €1.2M
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
54
Minutes
2,612
Goals
8
Assists
3
Started
31/54
Min / app
48
Cards
2Y 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 Jeong…

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 €3.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €3.5MModel A €4.7M

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 1,687 midfielders

Woo-yeong Jeong's percentiles among midfielders: Goals per 90 92nd, Assists per 90 54th, Minutes, two years 50th, Starts 31st, Minutes, last 365 days 43rd, European club minutes 30th92ndGoals54thAssists50thMinutes31stStarts43rdRecent30thEurope

Dashed ring: the midfielder median (50th percentile)

Goals per 90

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

0.28 this player0.08 midfielder median92nd percentile

0.00peer deciles · median line · this player ●0.93

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
€125k
Sept 2018
Peak
€5.5M
Dec 2021
Model target
€3.5M
May 2026
Valuations
21
5 club changes
May 2026€3.5M1.FC Union BerlinValuation the model is trained to reproduce

May 2026: €3.5M, 1.FC Union Berlin. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2018-09-07€125kFC Bayern Munich II
2018-12-18€700kFC Bayern Munich II
2019-05-02€2MFC Bayern Munich II
2019-06-05€2MFC Bayern Munich II
2019-12-17€2MSC Freiburg
2020-04-08€1.8MFC Bayern Munich II
2020-11-26€2.5MSC Freiburg
2021-02-10€3MSC Freiburg
2021-06-09€3MSC Freiburg
2021-10-07€4.5MSC Freiburg
2021-12-22€5.5MSC Freiburg
2022-06-09€5.5MSC Freiburg
2022-11-09€5.5MSC Freiburg
2023-03-29€4MSC Freiburg
2023-06-22€3.5MSC Freiburg
2023-12-14€3.5MVfB Stuttgart
2024-05-29€3.5MVfB Stuttgart
2024-12-20€4M1.FC Union Berlin
2025-06-05€4M1.FC Union Berlin
2025-12-19€3.5M1.FC Union Berlin
2026-05-27€3.5M1.FC Union Berlin

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
−0.291

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 37% of the 451 Bundesliga players.

€300k€2M€15M€100M€3.5MSee them in the Explorer →

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

Valued above 59% of the 1,687 midfielders.

€20k€200k€2M€20M€3.5MSee them in the Explorer →

Where Jeong 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).