FairValue

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Derrick

Köhn

LBGhana · 1.FC Union Berlin

№ 391780Established €4.8M −0.18

Player dossierBundesliga

DerrickKöhn

LBLeft-BackDefender

Club
1.FC Union Berlin
League
Bundesliga
Nationality
Ghana
Age
27
Height
180 cm
Foot
Left
Valued
27 May 2026

Reading the valuation

The market values Köhn at €4M. Model A, which never saw Köhn during training, estimates €4.8M: the market value is 16% below that estimate.

That is a factor of ×1.20. 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 €4.2M, closer to the market here, although it is usually further off (typical miss ×2.07).

A gap describes the model's arithmetic for this player's inputs, not what the player is worth.

▼ −0.18A €4.8M▼ −0.05B €4.2M
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
62
Minutes
3,721
Goals
3
Assists
4
Started
41/62
Min / app
60
Cards
7Y 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 Köhn…

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 €4M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €4MModel A €4.8M

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 2,065 defenders

Derrick Köhn's percentiles among defenders: Goals per 90 76th, Assists per 90 76th, Minutes, two years 65th, Starts 22nd, Minutes, last 365 days 58th, European club minutes 65th76thGoals76thAssists65thMinutes22ndStarts58thRecent65thEurope

Dashed ring: the defender median (50th percentile)

Goals per 90

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

0.07 this player0.03 defender median76th 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
€150k
Aug 2017
Peak
€6M
May 2024
Model target
€4M
May 2026
Valuations
24
5 club changes
May 2026€4M1.FC Union BerlinValuation the model is trained to reproduce

May 2026: €4M, 1.FC Union Berlin. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2017-08-20€150kFC Bayern Munich II
2018-02-20€250kFC Bayern Munich II
2018-09-07€300kFC Bayern Munich II
2019-07-12€350kFC Bayern Munich II
2019-12-11€450kFC Bayern Munich II
2020-04-03€550kFC Bayern Munich II
2020-04-08€500kFC Bayern Munich II
2020-07-01€800kWillem II Tilburg
2020-10-14€1MWillem II Tilburg
2021-03-09€800kWillem II Tilburg
2021-05-19€800kWillem II Tilburg
2022-01-05€650kWillem II Tilburg
2022-06-08€550kWillem II Tilburg
2022-09-28€1MHannover 96
2022-11-30€1.5MHannover 96
2023-06-28€2MHannover 96
2023-10-20€2.8MHannover 96
2023-12-15€3MHannover 96
2024-03-15€4.8MGalatasaray
2024-05-31€6MGalatasaray
2024-12-20€6MSV Werder Bremen
2025-06-05€5MSV Werder Bremen
2025-12-19€4M1.FC Union Berlin
2026-05-27€4M1.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
−0.179

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 39% of the 451 Bundesliga players.

€300k€2M€15M€100M€4MSee them in the Explorer →

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

Valued above 65% of the 2,065 defenders.

€20k€200k€2M€20M€4MSee them in the Explorer →

Where Köhn 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).