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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  • TerminalMarket LandscapeHow observed value is distributed, and where the model drifts.

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James

Brown

RBIreland · Kilmarnock FC

№ 437573Emerging €496k −0.91

Player dossierPremiership

JamesBrown

RBRight-BackDefender

Club
Kilmarnock FC
League
Premiership
Nationality
Ireland
Age
27
Height
–
Foot
Right
Valued
10 Dec 2025

Reading the valuation

The market values Brown at €200k. Model A, which never saw Brown during training, estimates €496k: the market value is 60% below that estimate.

That is a factor of ×2.48. 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 €750k, 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.

▼ −0.91A €496k▼ −1.32B €750k
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
53
Minutes
3,598
Goals
0
Assists
1
Started
37/53
Min / app
68
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 Brown…

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 €200k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €200kModel A €496k

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

James Brown's percentiles among defenders: Goals per 90 18th, Assists per 90 41st, Minutes, two years 63rd, Starts 27th, Minutes, last 365 days 49th, European club minutes 30th18thGoals41stAssists63rdMinutes27thStarts49thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

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

3,598 this player2,860 defender median63rd percentile

451peer deciles · median line · this player ●9,111

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
€25k
Aug 2021
Peak
€200k
Jun 2023
Model target
€200k
Dec 2025
Valuations
9
4 club changes
Dec 2025€200kKilmarnock FCValuation the model is trained to reproduce

Dec 2025: €200k, Kilmarnock FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2021-08-01€25kDrogheda United FC
2021-12-28€100kDrogheda United FC
2023-04-06€125kDoncaster Rovers
2023-06-16€200kBlackburn Rovers
2023-12-05€200kRoss County FC
2024-05-30€200kRoss County FC
2024-12-03€200kRoss County FC
2025-06-17€200kRoss County FC
2025-12-10€200kKilmarnock 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
−0.909

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 →

Premiership311 players · median €400k

Valued above 26% of the 311 Premiership players.

€20k€150k€1M€7.5M€200kSee them in the Explorer →

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

Valued above 5% of the 2,065 defenders.

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

Where Brown 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).