FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Portrait of Maximilian Mittelstädt

Maximilian

Mittelstädt

LBGermany · VfB Stuttgart

№ 282660Elite €21.9M −0.20

Image: FootyLogos

Player dossierBundesliga

MaximilianMittelstädt

LBLeft-BackDefender

Club
VfB Stuttgart
League
Bundesliga
Nationality
Germany
Age
29
Height
180 cm
Foot
Left
Valued
27 May 2026

Reading the valuation

The market values Mittelstädt at €18M. Model A, which never saw Mittelstädt during training, estimates €21.9M: the market value is 18% below that estimate.

That is a factor of ×1.22. 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 €22.8M, 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.

▼ −0.20A €21.9M▼ −0.24B €22.8M
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
93
Minutes
7,175
Goals
8
Assists
18
Started
81/93
Min / app
77
Cards
13Y 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 Mittelstädt…

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 €18M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €18MModel A €21.9M

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

Maximilian Mittelstädt's percentiles among defenders: Goals per 90 87th, Assists per 90 97th, Minutes, two years 98th, Starts 61st, Minutes, last 365 days 97th, European club minutes 86th87thGoals97thAssists98thMinutes61stStarts97thRecent86thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

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

7,175 this player2,860 defender median98th percentile

451peer deciles · median line · this player ●9,111

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
Aug 2015
Peak
€20M
Dec 2024
Model target
€18M
May 2026
Valuations
30
1 club change
May 2026€18MVfB StuttgartValuation the model is trained to reproduce

May 2026: €18M, VfB Stuttgart. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2015-08-20€100kHertha BSC
2016-02-15€125kHertha BSC
2016-07-22€500kHertha BSC
2017-02-07€500kHertha BSC
2017-03-22€750kHertha BSC
2017-06-19€1MHertha BSC
2017-12-28€1.5MHertha BSC
2018-06-05€2MHertha BSC
2018-10-22€4MHertha BSC
2018-12-18€6MHertha BSC
2019-03-06€9MHertha BSC
2019-06-05€11MHertha BSC
2019-12-17€14MHertha BSC
2020-04-08€11MHertha BSC
2020-09-16€10MHertha BSC
2021-02-10€8MHertha BSC
2021-06-09€7MHertha BSC
2021-10-07€4.5MHertha BSC
2021-12-22€4.5MHertha BSC
2022-06-09€4.5MHertha BSC
2022-09-21€3MHertha BSC
2022-11-09€2MHertha BSC
2023-06-22€2MHertha BSC
2023-12-14€5MVfB Stuttgart
2024-03-27€14MVfB Stuttgart
2024-05-29€17MVfB Stuttgart
2024-12-20€20MVfB Stuttgart
2025-06-05€20MVfB Stuttgart
2025-12-19€18MVfB Stuttgart
2026-05-27€18MVfB Stuttgart

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
−0.196

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 80% of the 451 Bundesliga players.

€300k€2M€15M€100M€18MSee them in the Explorer →

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

Valued above 89% of the 2,065 defenders.

€20k€200k€2M€20M€18MSee them in the Explorer →

Where Mittelstädt 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).