FairValue

Checking model

Esc
  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
  • EnvironmentTerminalExplore, compare and track players; market, league and model views.
  • EnvironmentStoriesValuations, head-to-heads and research findings, told as stories.
  • TerminalPlayer ExplorerSearch, filter and sort the player export.
  • TerminalComparison StudioTwo to four players on one scale.
  • TerminalWatchlistsNamed collections, kept in this browser.
  • TerminalMarket LandscapeHow observed value is distributed, and where the model drifts.

↑ ↓ to move · Enter to open · Esc to closeLoading player index…

Mario

Stroeykens

AMDR Congo · RSC Anderlecht

№ 588866Established €4M +0.12

Player dossierPro League

MarioStroeykens

AMAttacking MidfieldMidfield

Club
RSC Anderlecht
League
Pro League
Nationality
DR Congo
Age
21
Height
177 cm
Foot
Right
Valued
4 Jun 2026

Reading the valuation

The market values Stroeykens at €4.5M. Model A, which never saw Stroeykens during training, estimates €4M: the market value is 12% above that estimate.

That is a factor of ×1.12. 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 €9.6M, 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.

▲ +0.12A €4M▼ −0.76B €9.6M
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
60
Minutes
3,169
Goals
5
Assists
6
Started
36/60
Min / app
53
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 Stroeykens…

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 €4.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €4.5MModel A €4M

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

Mario Stroeykens's percentiles among midfielders: Goals per 90 70th, Assists per 90 77th, Minutes, two years 60th, Starts 34th, Minutes, last 365 days 32nd, European club minutes 92nd70thGoals77thAssists60thMinutes34thStarts32ndRecent92ndEurope

Dashed ring: the midfielder median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

26% this player0% midfielder median92nd 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
€500k
Mar 2021
Peak
€14M
Dec 2024
Model target
€4.5M
Jun 2026
Valuations
16
0 club changes
Jun 2026€4.5MRSC AnderlechtValuation the model is trained to reproduce

Jun 2026: €4.5M, RSC Anderlecht. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2021-03-17€500kRSC Anderlecht
2021-06-07€500kRSC Anderlecht
2022-01-06€500kRSC Anderlecht
2022-04-12€1MRSC Anderlecht
2022-09-07€2MRSC Anderlecht
2022-11-04€3.5MRSC Anderlecht
2023-06-09€3MRSC Anderlecht
2023-12-19€5.5MRSC Anderlecht
2024-03-22€8MRSC Anderlecht
2024-06-04€10MRSC Anderlecht
2024-12-11€14MRSC Anderlecht
2025-06-12€12MRSC Anderlecht
2025-10-01€10MRSC Anderlecht
2025-12-10€8MRSC Anderlecht
2026-03-13€6MRSC Anderlecht
2026-06-04€4.5MRSC Anderlecht

Audit context group-level, not about this player

Audit group
non-UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
+0.117

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 84% of the 350 Pro League players.

€100k€750k€5M€30M€4.5MSee them in the Explorer →

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

Valued above 64% of the 1,687 midfielders.

€20k€200k€2M€20M€4.5MSee them in the Explorer →

Where Stroeykens 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).