FairValue

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Wolke

Janssens

CBBelgium · Sint-Truidense VV

№ 235247Emerging €501k −0.51

Player dossierPro League

WolkeJanssens

CBCentre-BackDefender

Club
Sint-Truidense VV
League
Pro League
Nationality
Belgium
Age
31
Height
185 cm
Foot
Right
Valued
4 Jun 2026

Reading the valuation

The market values Janssens at €300k. Model A, which never saw Janssens during training, estimates €501k: the market value is 40% below that estimate.

That is a factor of ×1.67. Model A's typical held-out miss is ×1.50 either way, so this gap is larger than its usual error.

Without league and club, Model B estimates €582k, 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.

▼ −0.51A €501k▼ −0.66B €582k
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
21
Minutes
921
Goals
0
Assists
0
Started
9/21
Min / app
44
Cards
0Y 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 Janssens…

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 €300k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €300kModel A €501k

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

Wolke Janssens's percentiles among defenders: Goals per 90 18th, Assists per 90 17th, Minutes, two years 10th, Starts 4th, Minutes, last 365 days 2nd, European club minutes 30th18thGoals17thAssists10thMinutes4thStarts2ndRecent30thEurope

Dashed ring: the defender median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

0% this player0% defender median30th percentile

0%peer deciles · median line · this player ●85%

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
€75k
Oct 2014
Peak
€800k
Jun 2023
Model target
€300k
Jun 2026
Valuations
28
3 club changes
Jun 2026€300kSint-Truidense VVValuation the model is trained to reproduce

Jun 2026: €300k, Sint-Truidense VV. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2014-10-21€75kKFC Dessel Sport
2015-10-28€150kKFC Dessel Sport
2016-02-04€200kKFC Dessel Sport
2016-07-15€300kSint-Truidense VV
2017-01-21€300kSint-Truidense VV
2017-06-06€450kSint-Truidense VV
2017-10-25€400kLierse SK (-2018)
2018-04-05€350kLierse SK (-2018)
2018-09-11€300kSint-Truidense VV
2018-12-27€300kSint-Truidense VV
2019-06-10€250kSint-Truidense VV
2019-09-13€450kSint-Truidense VV
2019-12-13€550kSint-Truidense VV
2020-04-08€450kSint-Truidense VV
2020-10-16€500kSint-Truidense VV
2021-03-17€400kSint-Truidense VV
2021-06-07€350kSint-Truidense VV
2022-01-06€300kSint-Truidense VV
2022-04-12€400kSint-Truidense VV
2022-11-04€600kSint-Truidense VV
2023-06-09€800kSint-Truidense VV
2023-10-23€700kSint-Truidense VV
2023-12-19€500kSint-Truidense VV
2024-06-04€500kSint-Truidense VV
2024-12-11€400kSint-Truidense VV
2025-06-12€400kSint-Truidense VV
2025-12-10€300kSint-Truidense VV
2026-06-04€300kSint-Truidense VV

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
−0.513

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 →

Pro League350 players · median €1.8M

Valued above 3% of the 350 Pro League players.

€100k€750k€5M€30M€300kSee them in the Explorer →

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

Valued above 9% of the 2,065 defenders.

€20k€200k€2M€20M€300kSee them in the Explorer →

Where Janssens 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).