FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
  • EnvironmentTerminalExplore, compare and track players; market, league and model views.
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  • TerminalPlayer ExplorerSearch, filter and sort the player export.
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  • TerminalWatchlistsNamed collections, kept in this browser.
  • TerminalMarket LandscapeHow observed value is distributed, and where the model drifts.

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Rav van den

Berg

CBNetherlands · 1.FC Köln

№ 640556Established €3.3M +0.75

Player dossierBundesliga

Rav van denBerg

CBCentre-BackDefender

Club
1.FC Köln
League
Bundesliga
Nationality
Netherlands
Age
21
Height
191 cm
Foot
Right
Valued
27 May 2026

Reading the valuation

The market values Berg at €7M. Model A, which never saw Berg during training, estimates €3.3M: the market value is 111% above that estimate.

That is a factor of ×2.11. 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 €761k, 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.

▲ +0.75A €3.3M▲ +2.22B €761k
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
14
Minutes
1,132
Goals
0
Assists
1
Started
12/14
Min / app
81
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 Berg…

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 €7M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €7MModel 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

Rav van den Berg's percentiles among defenders: Goals per 90 18th, Assists per 90 71st, Minutes, two years 15th, Starts 57th, Minutes, last 365 days 32nd, European club minutes 30th18thGoals71stAssists15thMinutes57thStarts32ndRecent30thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.08 this player0.04 defender median71st 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
€75k
May 2021
Peak
€8M
Oct 2025
Model target
€7M
May 2026
Valuations
13
2 club changes
May 2026€7M1.FC KölnValuation the model is trained to reproduce

May 2026: €7M, 1.FC Köln. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2021-05-19€75kPEC Zwolle
2021-10-04€150kPEC Zwolle
2022-01-05€200kPEC Zwolle
2022-06-08€200kPEC Zwolle
2023-07-04€400kPEC Zwolle
2023-12-21€2.2MMiddlesbrough FC
2024-03-07€3.5MMiddlesbrough FC
2024-05-24€4MMiddlesbrough FC
2024-12-30€4MMiddlesbrough FC
2025-05-27€4.5MMiddlesbrough FC
2025-10-14€8M1.FC Köln
2025-12-19€8M1.FC Köln
2026-05-27€7M1.FC Köln

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
+0.747

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 56% of the 451 Bundesliga players.

€300k€2M€15M€100M€7MSee them in the Explorer →

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

Valued above 76% of the 2,065 defenders.

€20k€200k€2M€20M€7MSee them in the Explorer →

Where Berg 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).