FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Mario

Sauer

CMSlovakia · FC Toulouse

№ 710885Emerging €3.2M −0.75

Player dossierLigue 1

MarioSauer

CMCentral MidfieldMidfield

Club
FC Toulouse
League
Ligue 1
Nationality
Slovakia
Age
22
Height
180 cm
Foot
Right
Valued
1 Jun 2026

Reading the valuation

The market values Sauer at €1.5M. Model A, which never saw Sauer during training, estimates €3.2M: the market value is 53% below that estimate.

That is a factor of ×2.12. 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 €620k, 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.

▼ −0.75A €3.2M▲ +0.88B €620k
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
25
Minutes
638
Goals
1
Assists
0
Started
6/25
Min / app
26
Cards
4Y 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 Sauer…

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 €1.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1.5MModel A €3.2M

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

Mario Sauer's percentiles among midfielders: Goals per 90 69th, Assists per 90 8th, Minutes, two years 4th, Starts 3rd, Minutes, last 365 days 17th, European club minutes 30th69thGoals8thAssists4thMinutes3rdStarts17thRecent30thEurope

Dashed ring: the midfielder median (50th percentile)

Goals per 90

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

0.14 this player0.08 midfielder median69th percentile

0.00peer deciles · median line · this player ●0.93

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
Oct 2021
Peak
€2M
Jun 2025
Model target
€1.5M
Jun 2026
Valuations
12
2 club changes
Jun 2026€1.5MFC ToulouseValuation the model is trained to reproduce

Jun 2026: €1.5M, FC Toulouse. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2021-10-12€50kMSK Zilina B
2021-12-28€75kMSK Zilina B
2022-06-23€150kMSK Zilina B
2022-12-16€200kMSK Zilina B
2023-06-21€250kMSK Zilina
2023-12-27€350kMSK Zilina
2024-03-28€375kMSK Zilina
2024-06-07€1.3MMSK Zilina
2024-12-27€1.7MMSK Zilina
2025-06-20€2MMSK Zilina
2025-12-15€1.8MFC Toulouse
2026-06-01€1.5MFC Toulouse

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
−0.753

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 →

Ligue 1423 players · median €5M

Valued above 13% of the 423 Ligue 1 players.

€100k€750k€5M€30M€1.5MSee them in the Explorer →

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

Valued above 39% of the 1,687 midfielders.

€20k€200k€2M€20M€1.5MSee them in the Explorer →

Where Sauer 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).