FairValue

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Portrait of Marten de Roon

Marten de

Roon

DMNetherlands · Atalanta BC

№ 133179Established €2.5M +0.25

Close-up

Image: FootyLogos

Player dossierSerie A

Marten deRoon

DMDefensive MidfieldMidfield

Club
Atalanta BC
League
Serie A
Nationality
Netherlands
Age
35
Height
186 cm
Foot
Right
Valued
29 May 2026

Reading the valuation

The market values Roon at €3.2M. Model A, which never saw Roon during training, estimates €2.5M: the market value is 29% above that estimate.

That is a factor of ×1.29. 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 €3.1M, closer to the market here, although it is usually further off (typical miss ×2.07).

A gap describes the model's arithmetic for this player's inputs, not what the player is worth.

▲ +0.25A €2.5M▲ +0.03B €3.1M
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
100
Minutes
8,210
Goals
6
Assists
9
Started
94/100
Min / app
82
Cards
17Y 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 Roon…

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 €3.2M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €3.2MModel A €2.5M

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

Marten de Roon's percentiles among midfielders: Goals per 90 42nd, Assists per 90 52nd, Minutes, two years 100th, Starts 92nd, Minutes, last 365 days 98th, European club minutes 88th42ndGoals52ndAssists100thMinutes92ndStarts98thRecent88thEurope

Dashed ring: the midfielder median (50th percentile)

Minutes, two years

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

8,210 this player2,607 midfielder median100th percentile

451peer deciles · median line · this player ●9,624

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
Mar 2010
Peak
€24M
Jun 2019
Model target
€3.2M
May 2026
Valuations
36
5 club changes
May 2026€3.2MAtalanta BCValuation the model is trained to reproduce

May 2026: €3.2M, Atalanta BC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2010-03-28€50kSparta Rotterdam U19
2010-08-29€75kSparta Rotterdam
2011-01-05€100kSparta Rotterdam
2011-06-15€125kSparta Rotterdam
2012-10-09€400kSC Heerenveen
2013-01-16€600kSC Heerenveen
2013-06-12€750kSC Heerenveen
2014-02-11€1MSC Heerenveen
2014-08-11€1.3MSC Heerenveen
2015-02-16€1.3MSC Heerenveen
2015-07-01€1.3MSC Heerenveen
2015-11-05€2MAtalanta BC
2016-01-04€3.5MAtalanta BC
2016-04-01€5MAtalanta BC
2016-08-01€10MMiddlesbrough FC
2017-02-20€10MMiddlesbrough FC
2017-06-28€10MMiddlesbrough FC
2017-12-29€12MAtalanta BC
2018-06-07€14MAtalanta BC
2018-12-20€17MAtalanta BC
2019-06-06€24MAtalanta BC
2019-12-12€24MAtalanta BC
2020-04-08€19MAtalanta BC
2020-08-25€23MAtalanta BC
2020-12-29€23MAtalanta BC
2021-05-27€23MAtalanta BC
2021-12-28€20MAtalanta BC
2022-06-07€17MAtalanta BC
2022-11-11€12MAtalanta BC
2023-06-15€10MAtalanta BC
2023-12-20€8MAtalanta BC
2024-06-05€7MAtalanta BC
2024-12-18€7MAtalanta BC
2025-06-17€5MAtalanta BC
2025-12-23€3.5MAtalanta BC
2026-05-29€3.2MAtalanta BC

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
+0.255

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 →

Serie A507 players · median €5.5M

Valued above 34% of the 507 Serie A players.

€100k€750k€5M€30M€3.2MSee them in the Explorer →

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

Valued above 59% of the 1,687 midfielders.

€20k€200k€2M€20M€3.2MSee them in the Explorer →

Where Roon 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).