FairValue

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Mateusz

Wieteska

CBPoland · Cagliari Calcio

№ 208172Emerging €1.1M −0.14

Player dossierSerie A

MateuszWieteska

CBCentre-BackDefender

Club
Cagliari Calcio
League
Serie A
Nationality
Poland
Age
29
Height
187 cm
Foot
Right
Valued
21 May 2026

Reading the valuation

The market values Wieteska at €1M. Model A, which never saw Wieteska during training, estimates €1.1M: the market value is 13% below that estimate.

That is a factor of ×1.15. 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 €534k, 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.

▼ −0.14A €1.1M▲ +0.63B €534k
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
15
Minutes
1,013
Goals
0
Assists
0
Started
11/15
Min / app
68
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 Wieteska…

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 €1M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1MModel A €1.1M

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

Mateusz Wieteska's percentiles among defenders: Goals per 90 18th, Assists per 90 17th, Minutes, two years 13th, Starts 32nd, Minutes, last 365 days 2nd, European club minutes 30th18thGoals17thAssists13thMinutes32ndStarts2ndRecent30thEurope

Dashed ring: the defender median (50th percentile)

Starts

Share of appearances started rather than entered from the bench.

73% this player83% defender median32nd percentile

18%peer deciles · median line · this player ●100%

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
Jul 2014
Peak
€4M
Oct 2023
Model target
€1M
May 2026
Valuations
33
11 club changes
May 2026€1MCagliari CalcioValuation the model is trained to reproduce

May 2026: €1M, Cagliari Calcio. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2014-07-21€50kLegia Warszawa
2015-03-05€150kLegia Warszawa
2015-06-30€150kLegia Warszawa
2016-01-17€125kDolcan Zabki
2016-08-20€125kLegia Warszawa
2017-01-21€200kLegia Warszawa
2017-03-02€200kChrobry Glogow
2017-07-05€200kLegia Warszawa
2018-01-16€500kGórnik Zabrze
2018-07-03€1.5MLegia Warszawa
2019-01-25€1.5MLegia Warszawa
2019-06-29€2MLegia Warszawa
2020-01-15€1.6MLegia Warszawa
2020-04-08€1.3MLegia Warszawa
2020-08-18€1.5MLegia Warszawa
2021-01-19€1.2MLegia Warszawa
2021-05-21€900kLegia Warszawa
2021-10-15€1.2MLegia Warszawa
2021-12-31€1MLegia Warszawa
2022-04-07€1.3MLegia Warszawa
2022-06-14€1.3MLegia Warszawa
2022-09-19€2.5MClermont Foot 63
2022-11-02€3MClermont Foot 63
2023-06-27€3MClermont Foot 63
2023-10-11€4MCagliari Calcio
2023-12-20€3.5MCagliari Calcio
2024-06-05€3MCagliari Calcio
2024-12-18€2.2MCagliari Calcio
2025-05-23€2MPAOK Thessaloniki
2025-10-01€1.8MKocaelispor
2025-12-17€1.5MKocaelispor
2026-03-05€1.2MKocaelispor
2026-05-21€1MCagliari Calcio

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
−0.136

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 8% of the 507 Serie A players.

€100k€750k€5M€30M€1MSee them in the Explorer →

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

Valued above 35% of the 2,065 defenders.

€20k€200k€2M€20M€1MSee them in the Explorer →

Where Wieteska 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).