FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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  • TerminalMarket LandscapeHow observed value is distributed, and where the model drifts.

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Ortwin De

Wolf

GKBelgium · KV Mechelen

№ 450218Emerging €1M −0.72

Player dossierPro League

Ortwin DeWolf

GKGoalkeeperGoalkeeper

Club
KV Mechelen
League
Pro League
Nationality
Belgium
Age
29
Height
190 cm
Foot
Left
Valued
4 Jun 2026

Reading the valuation

The market values Wolf at €500k. Model A, which never saw Wolf during training, estimates €1M: the market value is 51% below that estimate.

That is a factor of ×2.05. 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 €1.2M, 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.

▼ −0.72A €1M▼ −0.88B €1.2M
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
38
Minutes
3,375
Started
37/38
Min / app
89
Cards
2Y 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 Wolf…

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 €500k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €500kModel A €1M

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 485 goalkeepers

Ortwin De Wolf's percentiles among goalkeepers: Minutes, two years 62nd, Starts 17th, Minutes, last 365 days 28th, European club minutes 32nd62ndMinutes17thStarts28thRecent32ndEurope

Dashed ring: the goalkeeper median (50th percentile)

Minutes, two years

Total club minutes in the two-year window: how much the player was used.

3,375 this player2,790 goalkeeper median62nd percentile

450peer deciles · median line · this player ●9,210

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 2017
Peak
€1.5M
Jun 2025
Model target
€500k
Jun 2026
Valuations
24
4 club changes
Jun 2026€500kKV MechelenValuation the model is trained to reproduce

Jun 2026: €500k, KV Mechelen. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2017-07-25€50kKSC Lokeren (-2020)
2018-01-09€150kKSC Lokeren (-2020)
2018-06-03€350kKSC Lokeren (-2020)
2018-09-11€500kKSC Lokeren (-2020)
2018-12-27€750kKSC Lokeren (-2020)
2019-06-10€750kKSC Lokeren (-2020)
2019-12-13€900kKAS Eupen
2020-04-08€725kKAS Eupen
2020-10-16€850kKAS Eupen
2021-06-07€850kRoyal Antwerp FC
2021-10-06€600kRoyal Antwerp FC
2022-01-06€550kRoyal Antwerp FC
2022-04-12€550kRoyal Antwerp FC
2022-11-04€500kRoyal Antwerp FC
2023-06-09€500kRoyal Antwerp FC
2023-10-23€400kRoyal Antwerp FC
2023-12-19€300kRoyal Antwerp FC
2024-06-20€300kZulte Waregem
2024-10-02€750kKV Mechelen
2024-12-11€1.2MKV Mechelen
2025-06-12€1.5MKV Mechelen
2025-12-10€1MKV Mechelen
2026-03-13€700kKV Mechelen
2026-06-04€500kKV Mechelen

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
−0.720

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 9% of the 350 Pro League players.

€100k€750k€5M€30M€500kSee them in the Explorer →

Goalkeepers, all leagues485 players · median €1M

Valued above 27% of the 485 goalkeepers.

€20k€200k€2M€20M€500kSee them in the Explorer →

Where Wolf 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).