FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
  • EnvironmentTerminalExplore, compare and track players; market, league and model views.
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  • 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.

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Portrait of Kobbie Mainoo

Kobbie

Mainoo

CMEngland · Manchester United

№ 820374World Class €49.2M +0.35

Image: FootyLogos

Player dossierPremier League

KobbieMainoo

CMCentral MidfieldMidfield

Club
Manchester United
League
Premier League
Nationality
England
Age
21
Height
184 cm
Foot
Right
Valued
3 Jun 2026

Reading the valuation

The market values Mainoo at €70M. Model A, which never saw Mainoo during training, estimates €49.2M: the market value is 42% above that estimate.

That is a factor of ×1.42. 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 €22.3M, 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.

▲ +0.35A €49.2M▲ +1.14B €22.3M
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
66
Minutes
3,841
Goals
3
Assists
4
Started
41/66
Min / app
58
Cards
10Y 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 Mainoo…

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 €70M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €70MModel A €49.2M

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 1,687 midfielders

Kobbie Mainoo's percentiles among midfielders: Goals per 90 44th, Assists per 90 50th, Minutes, two years 71st, Starts 37th, Minutes, last 365 days 58th, European club minutes 65th44thGoals50thAssists71stMinutes37thStarts58thRecent65thEurope

Dashed ring: the midfielder median (50th percentile)

Minutes, two years

Total club minutes in the two-year window: how much the player was used.

3,841 this player2,607 midfielder median71st percentile

451peer deciles · median line · this player ●9,624

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
€300k
Nov 2022
Peak
€70M
Jun 2026
Model target
€70M
Jun 2026
Valuations
13
1 club change
Jun 2026€70MManchester UnitedValuation the model is trained to reproduce

Jun 2026: €70M, Manchester United. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2022-11-03€300kManchester United U21
2023-03-16€800kManchester United
2023-06-20€800kManchester United
2023-12-19€6MManchester United
2024-03-14€35MManchester United
2024-05-27€50MManchester United
2024-07-18€55MManchester United
2024-12-16€55MManchester United
2025-05-30€50MManchester United
2025-10-17€45MManchester United
2025-12-09€40MManchester United
2026-03-09€50MManchester United
2026-06-03€70MManchester United

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
+0.352

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 League555 players · median €18M

Valued above 94% of the 555 Premier League players.

€150k€1M€7.5M€50M€70MSee them in the Explorer →

Midfielders, all leagues1,687 players · median €2M

Valued above 98% of the 1,687 midfielders.

€20k€200k€2M€20M€70MSee them in the Explorer →

Where Mainoo 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).