FairValue

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Olivier

Deman

LBBelgium · SV Werder Bremen

№ 621802Established €3.3M +0.06

Player dossierBundesliga

OlivierDeman

LBLeft-BackDefender

Club
SV Werder Bremen
League
Bundesliga
Nationality
Belgium
Age
26
Height
181 cm
Foot
Left
Valued
27 May 2026

Reading the valuation

The market values Deman at €3.5M. Model A, which never saw Deman during training, estimates €3.3M: the market value is 6% above that estimate.

That is a factor of ×1.06. 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 €1M, 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.

▲ +0.06A €3.3M▲ +1.21B €1M
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
38
Minutes
2,237
Goals
1
Assists
3
Started
24/38
Min / app
59
Cards
9Y 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 Deman…

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 €3.3M

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

Olivier Deman's percentiles among defenders: Goals per 90 57th, Assists per 90 82nd, Minutes, two years 38th, Starts 18th, Minutes, last 365 days 37th, European club minutes 30th57thGoals82ndAssists38thMinutes18thStarts37thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.12 this player0.04 defender median82nd percentile

0.00peer deciles · median line · this player ●0.58

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
€50k
Jul 2019
Peak
€6M
Dec 2023
Model target
€3.5M
May 2026
Valuations
19
3 club changes
May 2026€3.5MSV Werder BremenValuation the model is trained to reproduce

May 2026: €3.5M, SV Werder Bremen. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2019-07-24€50kCercle Brugge
2019-12-13€100kCercle Brugge
2020-10-16€100kCercle Brugge
2021-03-17€350kCercle Brugge
2021-06-07€600kCercle Brugge
2021-10-06€900kCercle Brugge
2022-01-06€1MCercle Brugge
2022-04-12€1.3MCercle Brugge
2022-11-04€1.2MCercle Brugge
2023-03-22€1.6MCercle Brugge
2023-06-09€3MCercle Brugge
2023-10-18€4.5MSV Werder Bremen
2023-12-14€6MSV Werder Bremen
2024-05-29€5MSV Werder Bremen
2024-10-09€4MSV Werder Bremen
2024-12-20€3MSV Werder Bremen
2025-06-12€3MRoyal Antwerp FC
2025-12-19€3MSV Werder Bremen
2026-05-27€3.5MSV Werder Bremen

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
+0.059

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 →

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

Valued above 63% of the 2,065 defenders.

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

Where Deman 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).