FairValue

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Jakob

Breum

AMDenmark · Go Ahead Eagles

№ 657957Established €4.2M +0.17

Player dossierEredivisie

JakobBreum

AMAttacking MidfieldMidfield

Club
Go Ahead Eagles
League
Eredivisie
Nationality
Denmark
Age
22
Height
178 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Breum at €5M. Model A, which never saw Breum during training, estimates €4.2M: the market value is 18% above that estimate.

That is a factor of ×1.18. 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 €15M, 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.

▲ +0.17A €4.2M▼ −1.10B €15M
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
68
Minutes
5,161
Goals
17
Assists
13
Started
60/68
Min / app
76
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 Breum…

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 €5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €5MModel A €4.2M

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 1,687 midfielders

Jakob Breum's percentiles among midfielders: Goals per 90 93rd, Assists per 90 89th, Minutes, two years 88th, Starts 84th, Minutes, last 365 days 84th, European club minutes 74th93rdGoals89thAssists88thMinutes84thStarts84thRecent74thEurope

Dashed ring: the midfielder median (50th percentile)

Goals per 90

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

0.30 this player0.08 midfielder median93rd 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
€100k
Jul 2020
Peak
€5M
Mar 2025
Model target
€5M
May 2026
Valuations
17
3 club changes
May 2026€5MGo Ahead EaglesValuation the model is trained to reproduce

May 2026: €5M, Go Ahead Eagles. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-07-30€100kOdense Boldklub Youth
2020-12-23€50kOdense Boldklub U19
2021-06-04€50kOdense Boldklub U19
2021-10-06€150kOdense Boldklub U19
2021-12-28€150kOdense Boldklub U19
2022-06-20€500kOdense Boldklub
2022-12-22€450kOdense Boldklub
2023-06-26€450kOdense Boldklub
2023-12-15€650kGo Ahead Eagles
2024-03-18€900kGo Ahead Eagles
2024-05-31€1MGo Ahead Eagles
2024-10-14€1.5MGo Ahead Eagles
2024-12-17€2.3MGo Ahead Eagles
2025-03-28€5MGo Ahead Eagles
2025-05-28€5MGo Ahead Eagles
2025-12-02€4.5MGo Ahead Eagles
2026-05-28€5MGo Ahead Eagles

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
+0.165

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 →

Eredivisie425 players · median €1M

Valued above 80% of the 425 Eredivisie players.

€75k€500k€3M€20M€5MSee them in the Explorer →

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

Valued above 65% of the 1,687 midfielders.

€20k€200k€2M€20M€5MSee them in the Explorer →

Where Breum 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).