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…

Maxim

Leitsch

CBGermany · 1.FSV Mainz 05

№ 334207Emerging €1.3M −0.46

Player dossierBundesliga

MaximLeitsch

CBCentre-BackDefender

Club
1.FSV Mainz 05
League
Bundesliga
Nationality
Germany
Age
28
Height
189 cm
Foot
Left
Valued
27 May 2026

Reading the valuation

The market values Leitsch at €800k. Model A, which never saw Leitsch during training, estimates €1.3M: the market value is 37% below that estimate.

That is a factor of ×1.59. 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 €901k, 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.

▼ −0.46A €1.3M▼ −0.12B €901k
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
21
Minutes
1,061
Goals
1
Assists
0
Started
10/21
Min / app
51
Cards
2Y 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 Leitsch…

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 €800k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €800kModel A €1.3M

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

Maxim Leitsch's percentiles among defenders: Goals per 90 81st, Assists per 90 17th, Minutes, two years 14th, Starts 6th, Minutes, last 365 days 6th, European club minutes 61st81stGoals17thAssists14thMinutes6thStarts6thRecent61stEurope

Dashed ring: the defender median (50th percentile)

Goals per 90

Club goals per 90 minutes played in the two years to the valuation date.

0.08 this player0.03 defender median81st percentile

0.00peer deciles · median line · this player ●0.41

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
€100k
Jul 2016
Peak
€5M
Mar 2022
Model target
€800k
May 2026
Valuations
31
2 club changes
May 2026€800k1.FSV Mainz 05Valuation the model is trained to reproduce

May 2026: €800k, 1.FSV Mainz 05. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-07-22€100kVfL Bochum U19
2017-01-23€200kVfL Bochum U19
2017-06-27€200kVfL Bochum U19
2018-01-22€350kVfL Bochum
2018-06-19€350kVfL Bochum
2018-10-16€850kVfL Bochum
2019-01-08€850kVfL Bochum
2019-06-12€600kVfL Bochum
2019-09-25€450kVfL Bochum
2019-12-13€350kVfL Bochum
2020-04-02€600kVfL Bochum
2020-04-08€525kVfL Bochum
2020-07-15€750kVfL Bochum
2020-11-18€1.2MVfL Bochum
2021-02-08€2MVfL Bochum
2021-06-16€2.5MVfL Bochum
2021-12-22€2.5MVfL Bochum
2022-03-24€5MVfL Bochum
2022-06-09€5MVfL Bochum
2022-11-09€5M1.FSV Mainz 05
2023-03-29€3.5M1.FSV Mainz 05
2023-06-22€2M1.FSV Mainz 05
2023-12-14€2M1.FSV Mainz 05
2024-03-27€1.5M1.FSV Mainz 05
2024-05-29€1.5M1.FSV Mainz 05
2024-10-09€2M1.FSV Mainz 05
2024-12-20€2M1.FSV Mainz 05
2025-06-05€1.5M1.FSV Mainz 05
2025-12-19€1.5M1.FSV Mainz 05
2026-03-20€1M1.FSV Mainz 05
2026-05-27€800k1.FSV Mainz 05

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
−0.461

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 5% of the 451 Bundesliga players.

€300k€2M€15M€100M€800kSee them in the Explorer →

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

Valued above 29% of the 2,065 defenders.

€20k€200k€2M€20M€800kSee them in the Explorer →

Where Leitsch 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).