FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Portrait of Reece James

Reece

James

RBEngland · Chelsea FC

№ 472423World Class €31.6M +0.64

Image: FootyLogos

Player dossierPremier League

ReeceJames

RBRight-BackDefender

Club
Chelsea FC
League
Premier League
Nationality
England
Age
26
Height
180 cm
Foot
Right
Valued
3 Jun 2026

Reading the valuation

The market values James at €60M. Model A, which never saw James during training, estimates €31.6M: the market value is 90% above that estimate.

That is a factor of ×1.90. 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 €18.3M, 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.

▲ +0.64A €31.6M▲ +1.19B €18.3M
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
63
Minutes
3,980
Goals
4
Assists
9
Started
45/63
Min / app
63
Cards
7Y 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 James…

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 €60M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €60MModel A €31.6M

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

Reece James's percentiles among defenders: Goals per 90 84th, Assists per 90 96th, Minutes, two years 69th, Starts 29th, Minutes, last 365 days 86th, European club minutes 86th84thGoals96thAssists69thMinutes29thStarts86thRecent86thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.20 this player0.04 defender median96th percentile

0.00peer deciles · median line · this player ●0.58

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
Sept 2018
Peak
€70M
Nov 2022
Model target
€60M
Jun 2026
Valuations
25
2 club changes
Jun 2026€60MChelsea FCValuation the model is trained to reproduce

Jun 2026: €60M, Chelsea FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2018-09-24€250kWigan Athletic
2019-02-27€1MWigan Athletic
2019-06-13€7MChelsea FC U23
2019-12-10€15MChelsea FC
2020-03-09€25MChelsea FC
2020-04-08€22.5MChelsea FC
2020-10-13€30MChelsea FC
2020-12-17€35MChelsea FC
2021-03-18€40MChelsea FC
2021-05-28€40MChelsea FC
2021-10-05€45MChelsea FC
2021-12-23€55MChelsea FC
2022-06-15€60MChelsea FC
2022-11-03€70MChelsea FC
2023-06-20€65MChelsea FC
2023-10-09€55MChelsea FC
2023-12-19€50MChelsea FC
2024-05-27€40MChelsea FC
2024-10-01€35MChelsea FC
2024-12-16€30MChelsea FC
2025-05-30€30MChelsea FC
2025-10-17€35MChelsea FC
2025-12-09€50MChelsea FC
2026-03-09€60MChelsea FC
2026-06-03€60MChelsea 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
+0.640

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 92% of the 555 Premier League players.

€150k€1M€7.5M€50M€60MSee them in the Explorer →

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

Valued above 99% of the 2,065 defenders.

€20k€200k€2M€20M€60MSee them in the Explorer →

Where James 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).