FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Portrait of Wojciech Szczesny

Wojciech

Szczesny

GKPoland · FC Barcelona

№ 44058Emerging €1.7M −0.76

Image: FootyLogos

Player dossierLaLiga

WojciechSzczesny

GKGoalkeeperGoalkeeper

Club
FC Barcelona
League
LaLiga
Nationality
Poland
Age
36
Height
195 cm
Foot
Right
Valued
5 Jun 2026

Reading the valuation

The market values Szczesny at €800k. Model A, which never saw Szczesny during training, estimates €1.7M: the market value is 53% below that estimate.

That is a factor of ×2.13. 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 €868k, 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.

▼ −0.76A €1.7M▼ −0.08B €868k
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
42
Minutes
3,724
Started
41/42
Min / app
89
Cards
1Y 1R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Szczesny…

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 €1.7M

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

Wojciech Szczesny's percentiles among goalkeepers: Minutes, two years 65th, Starts 19th, Minutes, last 365 days 38th, European club minutes 92nd65thMinutes19thStarts38thRecent92ndEurope

Dashed ring: the goalkeeper median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

28% this player0% goalkeeper median92nd 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
€100k
Mar 2007
Peak
€40M
Dec 2019
Model target
€800k
Jun 2026
Valuations
43
6 club changes
Jun 2026€800kFC BarcelonaValuation the model is trained to reproduce

Jun 2026: €800k, FC Barcelona. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2007-03-09€100kArsenal FC U18
2008-03-19€100kArsenal FC U18
2009-08-06€50kArsenal FC
2009-11-23€400kBrentford FC
2010-04-21€475kBrentford FC
2010-09-25€525kArsenal FC
2011-02-01€2MArsenal FC
2011-08-08€5.5MArsenal FC
2012-02-06€12MArsenal FC
2012-06-24€14MArsenal FC
2013-01-28€15MArsenal FC
2013-07-02€14MArsenal FC
2014-01-15€15MArsenal FC
2014-08-12€16MArsenal FC
2015-02-12€14MArsenal FC
2015-07-01€10MArsenal FC
2016-01-04€10MAS Roma
2016-06-01€12MAS Roma
2016-08-01€12MAS Roma
2017-01-02€14MAS Roma
2017-06-08€17MAS Roma
2017-12-29€18MJuventus FC
2018-03-24€20MJuventus FC
2018-06-07€20MJuventus FC
2018-12-20€30MJuventus FC
2019-06-06€35MJuventus FC
2019-12-12€40MJuventus FC
2020-04-08€32MJuventus FC
2020-08-25€35MJuventus FC
2020-12-29€35MJuventus FC
2021-05-31€25MJuventus FC
2021-10-14€15MJuventus FC
2021-12-28€15MJuventus FC
2022-06-07€15MJuventus FC
2022-11-11€13MJuventus FC
2023-06-15€10MJuventus FC
2023-12-20€8MJuventus FC
2024-06-05€6MJuventus FC
2024-10-11€3MFC Barcelona
2024-12-27€1MFC Barcelona
2025-06-09€1MFC Barcelona
2025-12-12€900kFC Barcelona
2026-06-05€800kFC Barcelona

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
−0.757

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 →

LaLiga509 players · median €4M

Valued above 5% of the 509 LaLiga players.

€100k€1M€10M€100M€800kSee them in the Explorer →

Goalkeepers, all leagues485 players · median €1M

Valued above 39% of the 485 goalkeepers.

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

Where Szczesny 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).