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…

Marius

Müller

GKGermany · VfL Wolfsburg

№ 118161Emerging €434k +0.48

Player dossierBundesliga

MariusMüller

GKGoalkeeperGoalkeeper

Club
VfL Wolfsburg
League
Bundesliga
Nationality
Germany
Age
32
Height
192 cm
Foot
Right
Valued
27 May 2026

Reading the valuation

The market values Müller at €700k. Model A, which never saw Müller during training, estimates €434k: the market value is 61% above that estimate.

That is a factor of ×1.61. 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 €461k, 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.

▲ +0.48A €434k▲ +0.42B €461k
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
8
Minutes
654
Started
7/8
Min / app
82
Cards
1Y 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 Müller…

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 €700k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €700kModel A €434k

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

Marius Müller's percentiles among goalkeepers: Minutes, two years 9th, Starts 5th, Minutes, last 365 days 6th, European club minutes 32nd9thMinutes5thStarts6thRecent32ndEurope

Dashed ring: the goalkeeper median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

0% this player0% goalkeeper median32nd percentile

0%peer deciles · median line · this player ●86%

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
Jun 2012
Peak
€2M
Jan 2020
Model target
€700k
May 2026
Valuations
37
7 club changes
May 2026€700kVfL WolfsburgValuation the model is trained to reproduce

May 2026: €700k, VfL Wolfsburg. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2012-06-29€50k1.FC Kaiserslautern U19
2012-07-05€100k1.FC Kaiserslautern
2013-01-04€100k1.FC Kaiserslautern
2013-06-29€200k1.FC Kaiserslautern
2014-01-20€300k1.FC Kaiserslautern
2014-06-30€400k1.FC Kaiserslautern
2015-01-13€400k1.FC Kaiserslautern
2015-07-01€400k1.FC Kaiserslautern
2015-10-22€900k1.FC Kaiserslautern
2016-02-11€1M1.FC Kaiserslautern
2016-07-22€1.5MRB Leipzig
2017-02-07€1MRB Leipzig
2017-06-19€750kRB Leipzig
2018-01-22€750k1.FC Kaiserslautern
2018-06-19€750k1.FC Kaiserslautern
2018-08-22€500kRB Leipzig
2018-12-18€500kRB Leipzig
2019-06-05€500kRB Leipzig
2019-10-07€1.5MFC Luzern
2020-01-06€2MFC Luzern
2020-04-08€1.6MFC Luzern
2020-07-31€2MFC Luzern
2020-12-28€2MFC Luzern
2021-04-15€1.8MFC Luzern
2021-06-23€2MFC Luzern
2022-01-03€1.5MFC Luzern
2022-06-08€1MFC Luzern
2022-11-10€1MFC Luzern
2023-06-07€1MFC Luzern
2023-12-15€1MFC Schalke 04
2024-03-22€800kFC Schalke 04
2024-06-06€1MFC Schalke 04
2024-10-09€1.5MVfL Wolfsburg
2024-12-20€1.5MVfL Wolfsburg
2025-06-05€1.5MVfL Wolfsburg
2025-12-19€1MVfL Wolfsburg
2026-05-27€700kVfL Wolfsburg

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
+0.478

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 3% of the 451 Bundesliga players.

€300k€2M€15M€100M€700kSee them in the Explorer →

Goalkeepers, all leagues485 players · median €1M

Valued above 35% of the 485 goalkeepers.

€20k€200k€2M€20M€700kSee them in the Explorer →

Where Müller 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).