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…

Jesse

Joronen

GKFinland · Palermo FC

№ 131758Emerging €629k −0.23

Player dossierSerie A

JesseJoronen

GKGoalkeeperGoalkeeper

Club
Palermo FC
League
Serie A
Nationality
Finland
Age
33
Height
197 cm
Foot
Right
Valued
4 Jun 2026

Reading the valuation

The market values Joronen at €500k. Model A, which never saw Joronen during training, estimates €629k: the market value is 21% below that estimate.

That is a factor of ×1.26. 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 €355k, 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.

▼ −0.23A €629k▲ +0.34B €355k
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
10
Minutes
882
Started
9/10
Min / app
88
Cards
0Y 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 Joronen…

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 €500k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €500kModel A €629k

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

Jesse Joronen's percentiles among goalkeepers: Minutes, two years 14th, Starts 6th, Minutes, last 365 days 6th, European club minutes 32nd14thMinutes6thStarts6thRecent32ndEurope

Dashed ring: the goalkeeper median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

0% this player0% goalkeeper median32nd 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
€250k
Aug 2014
Peak
€5M
Oct 2019
Model target
€500k
Jun 2026
Valuations
26
5 club changes
Jun 2026€500kPalermo FCValuation the model is trained to reproduce

Jun 2026: €500k, Palermo FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2014-08-19€250kFulham FC
2015-02-24€250kFulham FC
2016-04-20€250kFulham FC
2016-09-01€250kFulham FC
2017-02-27€250kFulham FC
2017-12-18€700kAC Horsens
2018-06-01€700kAC Horsens
2018-12-21€1.5MFC Copenhagen
2019-06-08€2.5MFC Copenhagen
2019-10-08€5MBrescia Calcio (- 2025)
2019-12-12€5MBrescia Calcio (- 2025)
2020-04-08€4MBrescia Calcio (- 2025)
2020-08-25€4MBrescia Calcio (- 2025)
2021-02-22€2MBrescia Calcio (- 2025)
2021-05-26€1.7MBrescia Calcio (- 2025)
2021-12-29€1.5MBrescia Calcio (- 2025)
2022-06-06€1.4MBrescia Calcio (- 2025)
2022-12-22€1.2MVenezia FC
2023-06-12€1MVenezia FC
2023-12-27€800kVenezia FC
2024-06-03€1MVenezia FC
2024-12-18€1MVenezia FC
2025-03-25€600kVenezia FC
2025-06-17€500kVenezia FC
2025-12-11€500kPalermo FC
2026-06-04€500kPalermo 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
−0.230

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 1% of the 507 Serie A players.

€100k€750k€5M€30M€500kSee them in the Explorer →

Goalkeepers, all leagues485 players · median €1M

Valued above 27% of the 485 goalkeepers.

€20k€200k€2M€20M€500kSee them in the Explorer →

Where Joronen 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).