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…

Portrait of Mattia Perin

Mattia

Perin

GKItaly · Juventus FC

№ 110923Established €1.9M +0.03

Close-up

Image: FootyLogos

Player dossierSerie A

MattiaPerin

GKGoalkeeperGoalkeeper

Club
Juventus FC
League
Serie A
Nationality
Italy
Age
33
Height
188 cm
Foot
Right
Valued
29 May 2026

Reading the valuation

The market values Perin at €2M. Model A, which never saw Perin during training, estimates €1.9M: the market value is 3% above that estimate.

That is a factor of ×1.03. 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 €1.2M, 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.

▲ +0.03A €1.9M▲ +0.49B €1.2M
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
23
Minutes
1,995
Started
22/23
Min / app
87
Cards
1Y 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 Perin…

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 €2M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €2MModel A €1.9M

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 485 goalkeepers

Mattia Perin's percentiles among goalkeepers: Minutes, two years 39th, Starts 14th, Minutes, last 365 days 43rd, European club minutes 94th39thMinutes14thStarts43rdRecent94thEurope

Dashed ring: the goalkeeper median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

30% this player0% goalkeeper median94th 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
Sept 2009
Peak
€18M
Jan 2017
Model target
€2M
May 2026
Valuations
43
7 club changes
May 2026€2MJuventus FCValuation the model is trained to reproduce

May 2026: €2M, Juventus FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2009-09-21€100kGenoa U19
2009-10-23€200kGenoa U19
2009-10-28€300kGenoa U19
2010-07-19€500kGenoa CFC
2011-01-10€700kGenoa CFC
2011-06-21€800kGenoa CFC
2012-01-01€1MCalcio Padova
2012-06-12€2.5MCalcio Padova
2012-11-07€7MDelfino Pescara 1936
2013-01-14€8.5MDelfino Pescara 1936
2013-06-19€6.5MDelfino Pescara 1936
2014-01-07€8MGenoa CFC
2014-03-10€10MGenoa CFC
2014-07-11€12MGenoa CFC
2014-11-08€14MGenoa CFC
2015-01-07€15MGenoa CFC
2015-07-01€17.5MGenoa CFC
2016-01-04€17.5MGenoa CFC
2016-07-15€17.5MGenoa CFC
2017-01-02€18MGenoa CFC
2017-03-28€15MGenoa CFC
2017-06-08€15MGenoa CFC
2017-12-29€15MGenoa CFC
2018-06-07€16MGenoa CFC
2018-12-20€15MJuventus FC
2019-06-06€13MJuventus FC
2019-10-08€10MJuventus FC
2019-12-12€10MJuventus FC
2020-04-08€8MGenoa CFC
2020-08-25€7.5MGenoa CFC
2020-12-29€7MGenoa CFC
2021-06-03€7MGenoa CFC
2021-10-14€5MJuventus FC
2021-12-28€4MJuventus FC
2022-06-07€4MJuventus FC
2022-11-11€4MJuventus FC
2023-06-15€4MJuventus FC
2023-12-20€3MJuventus FC
2024-06-05€3MJuventus FC
2024-12-18€3MJuventus FC
2025-06-17€2.5MJuventus FC
2025-12-23€2MJuventus FC
2026-05-29€2MJuventus FC

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
+0.029

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 20% of the 507 Serie A players.

€100k€750k€5M€30M€2MSee them in the Explorer →

Goalkeepers, all leagues485 players · median €1M

Valued above 59% of the 485 goalkeepers.

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

Where Perin 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).