FairValue

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Mats

Hummels

CBGermany · AS Roma

№ 39728Established €2.1M −0.05

Player dossierSerie A

MatsHummels

CBCentre-BackDefender

Club
AS Roma
League
Serie A
Nationality
Germany
Age
36
Height
191 cm
Foot
Right
Valued
17 Jun 2025

Reading the valuation

The market values Hummels at €2M. Model A, which never saw Hummels during training, estimates €2.1M: the market value is 5% below that estimate.

That is a factor of ×1.05. 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 €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.

▼ −0.05A €2.1M▲ +0.48B €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
60
Minutes
4,284
Goals
5
Assists
1
Started
52/60
Min / app
71
Cards
11Y 2R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Hummels…

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 €2M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €2MModel A €2.1M

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 2,065 defenders

Mats Hummels's percentiles among defenders: Goals per 90 88th, Assists per 90 38th, Minutes, two years 74th, Starts 60th, Minutes, last 365 days 39th, European club minutes 97th88thGoals38thAssists74thMinutes60thStarts39thRecent97thEurope

Dashed ring: the defender median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

36% this player0% defender median97th 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
€50k
May 2006
Peak
€60M
Apr 2018
Model target
€2M
Jun 2025
Valuations
46
6 club changes
Jun 2025€2MAS RomaValuation the model is trained to reproduce

Jun 2025: €2M, AS Roma. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2006-05-27€50kFC Bayern Munich U19
2006-10-01€150kFC Bayern Munich II
2007-01-15€250kBayern Munich
2008-03-05€600kBorussia Dortmund
2008-06-04€1MBorussia Dortmund
2008-08-31€2.5MBorussia Dortmund
2009-01-21€4MBorussia Dortmund
2009-07-10€4.5MBorussia Dortmund
2009-11-18€5.5MBorussia Dortmund
2010-01-17€8MBorussia Dortmund
2010-05-08€10MBorussia Dortmund
2011-01-12€13MBorussia Dortmund
2011-03-01€15MBorussia Dortmund
2011-06-29€18MBorussia Dortmund
2012-01-23€20MBorussia Dortmund
2012-06-29€24MBorussia Dortmund
2013-01-13€24MBorussia Dortmund
2013-06-30€26MBorussia Dortmund
2014-07-10€35MBorussia Dortmund
2015-02-04€35MBorussia Dortmund
2015-07-01€35MBorussia Dortmund
2016-02-15€32MBorussia Dortmund
2016-06-01€38MBorussia Dortmund
2016-07-22€38MBayern Munich
2017-02-07€38MBayern Munich
2017-06-19€40MBayern Munich
2017-12-28€40MBayern Munich
2018-04-04€60MBayern Munich
2018-06-05€60MBayern Munich
2018-10-22€55MBayern Munich
2018-12-18€40MBayern Munich
2019-06-05€35MBayern Munich
2019-12-17€30MBorussia Dortmund
2020-04-08€24MBorussia Dortmund
2020-09-16€20MBorussia Dortmund
2021-02-10€15MBorussia Dortmund
2021-06-01€12MBorussia Dortmund
2021-12-22€9MBorussia Dortmund
2022-06-09€6.5MBorussia Dortmund
2022-11-09€6.5MBorussia Dortmund
2023-06-22€6MBorussia Dortmund
2023-12-14€6MBorussia Dortmund
2024-05-29€5MBorussia Dortmund
2024-12-18€3.5MAS Roma
2025-03-25€2.5MAS Roma
2025-06-17€2MAS Roma

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
−0.053

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 20% of the 507 Serie A players.

€100k€750k€5M€30M€2MSee them in the Explorer →

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

Valued above 49% of the 2,065 defenders.

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

Where Hummels 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).