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…

Lucas

Fasson

CBBrazil · Lokomotiv Moscow

№ 729266Established €5.2M −0.03

Player dossierPremier Liga

LucasFasson

CBCentre-BackDefender

Club
Lokomotiv Moscow
League
Premier Liga
Nationality
Brazil
Age
24
Height
187 cm
Foot
Left
Valued
26 May 2026

Reading the valuation

The market values Fasson at €5M. Model A, which never saw Fasson during training, estimates €5.2M: the market value is 3% below 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 €2.1M, 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 €5.2M▲ +0.89B €2.1M
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
47
Minutes
3,548
Goals
2
Assists
3
Started
38/47
Min / app
75
Cards
5Y 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 Fasson…

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 €5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €5MModel A €5.2M

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 2,065 defenders

Lucas Fasson's percentiles among defenders: Goals per 90 64th, Assists per 90 70th, Minutes, two years 62nd, Starts 47th, Minutes, last 365 days 74th, European club minutes 30th64thGoals70thAssists62ndMinutes47thStarts74thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, last 365 days

Club minutes in the final year of the window: recent involvement, or the absence of it.

2,433 this player1,687 defender median74th percentile

0peer deciles · median line · this player ●4,941

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
Nov 2020
Peak
€5M
May 2026
Model target
€5M
May 2026
Valuations
14
2 club changes
May 2026€5MLokomotiv MoscowValuation the model is trained to reproduce

May 2026: €5M, Lokomotiv Moscow. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-11-10€50kDeportes La Serena
2021-03-11€650kDeportes La Serena
2021-12-17€1.5MClub Athletico Paranaense
2022-04-06€1.5MClub Athletico Paranaense
2022-08-19€2.5MLokomotiv Moscow
2022-11-21€2.5MLokomotiv Moscow
2023-06-14€2MLokomotiv Moscow
2023-10-05€3MLokomotiv Moscow
2023-12-13€3.5MLokomotiv Moscow
2024-06-04€3.5MLokomotiv Moscow
2024-12-12€3MLokomotiv Moscow
2025-06-04€3MLokomotiv Moscow
2025-12-16€4MLokomotiv Moscow
2026-05-26€5MLokomotiv Moscow

Audit context group-level, not about this player

Audit group
non-UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
−0.031

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 →

Premier Liga412 players · median €1M

Valued above 86% of the 412 Premier Liga players.

€50k€300k€2M€15M€5MSee them in the Explorer →

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

Valued above 70% of the 2,065 defenders.

€20k€200k€2M€20M€5MSee them in the Explorer →

Where Fasson 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).