FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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William

Bøving

CFDenmark · 1.FSV Mainz 05

№ 610400Established €2.5M +0.35

Player dossierBundesliga

WilliamBøving

CFCentre-ForwardAttack

Club
1.FSV Mainz 05
League
Bundesliga
Nationality
Denmark
Age
23
Height
176 cm
Foot
Both
Valued
27 May 2026

Reading the valuation

The market values Bøving at €3.5M. Model A, which never saw Bøving during training, estimates €2.5M: the market value is 42% above that estimate.

That is a factor of ×1.42. 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 €1.4M, 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.

▲ +0.35A €2.5M▲ +0.89B €1.4M
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
20
Minutes
1,062
Goals
0
Assists
3
Started
12/20
Min / app
53
Cards
1Y 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 Bøving…

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 €2.5M

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 1,583 attackers

William Bøving's percentiles among attackers: Goals per 90 3rd, Assists per 90 84th, Minutes, two years 21st, Starts 52nd, Minutes, last 365 days 10th, European club minutes 100th3rdGoals84thAssists21stMinutes52ndStarts10thRecent100thEurope

Dashed ring: the attacker median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

79% this player0% attacker median100th percentile

0%peer deciles · median line · this player ●100%

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
Mar 2020
Peak
€8M
Jun 2025
Model target
€3.5M
May 2026
Valuations
17
3 club changes
May 2026€3.5M1.FSV Mainz 05Valuation the model is trained to reproduce

May 2026: €3.5M, 1.FSV Mainz 05. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-03-09€150kFC Copenhagen U19
2020-07-31€150kFC Copenhagen U19
2020-12-23€100kFC Copenhagen U19
2021-06-04€100kFC Copenhagen U19
2021-10-06€1MFC Copenhagen
2021-12-28€2.5MFC Copenhagen
2022-06-20€2.5MFC Copenhagen
2022-11-10€3MSK Sturm Graz
2023-06-12€3MSK Sturm Graz
2023-12-11€3MSK Sturm Graz
2024-03-11€2.5MSK Sturm Graz
2024-05-21€3.5MSK Sturm Graz
2024-12-17€5MSK Sturm Graz
2025-06-06€8MSK Sturm Graz
2025-12-19€5M1.FSV Mainz 05
2026-03-20€3.5M1.FSV Mainz 05
2026-05-27€3.5M1.FSV Mainz 05

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
+0.353

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 →

Attackers, all leagues1,583 players · median €2.5M

Valued above 56% of the 1,583 attackers.

€20k€300k€5M€75M€3.5MSee them in the Explorer →

Where Bøving 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).