FairValue

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Portrait of Aaron Hickey

Aaron

Hickey

RBScotland · Brentford FC

№ 591949Elite €11.1M +0.37

Image: FootyLogos

Player dossierPremier League

AaronHickey

RBRight-BackDefender

Club
Brentford FC
League
Premier League
Nationality
Scotland
Age
23
Height
185 cm
Foot
Both
Valued
3 Jun 2026

Reading the valuation

The market values Hickey at €16M. Model A, which never saw Hickey during training, estimates €11.1M: the market value is 45% above that estimate.

That is a factor of ×1.45. 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 €1.1M, 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.

▲ +0.37A €11.1M▲ +2.70B €1.1M
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
26
Minutes
1,018
Goals
1
Assists
0
Started
12/26
Min / app
39
Cards
1Y 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 Hickey…

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 €16M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €16MModel A €11.1M

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

Aaron Hickey's percentiles among defenders: Goals per 90 83rd, Assists per 90 17th, Minutes, two years 13th, Starts 5th, Minutes, last 365 days 29th, European club minutes 30th83rdGoals17thAssists13thMinutes5thStarts29thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Goals per 90

Club goals per 90 minutes played in the two years to the valuation date.

0.09 this player0.03 defender median83rd percentile

0.00peer deciles · median line · this player ●0.41

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
€150k
Aug 2019
Peak
€30M
Oct 2023
Model target
€16M
Jun 2026
Valuations
23
2 club changes
Jun 2026€16MBrentford FCValuation the model is trained to reproduce

Jun 2026: €16M, Brentford FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2019-08-20€150kHeart of Midlothian FC
2020-02-05€600kHeart of Midlothian FC
2020-04-08€525kHeart of Midlothian FC
2020-07-21€600kHeart of Midlothian FC
2020-10-29€2.5MBologna FC 1909
2020-12-29€5MBologna FC 1909
2021-06-03€5MBologna FC 1909
2021-10-14€8MBologna FC 1909
2021-12-28€13MBologna FC 1909
2022-03-15€15MBologna FC 1909
2022-06-07€18MBologna FC 1909
2022-11-03€18MBrentford FC
2023-06-20€25MBrentford FC
2023-10-09€30MBrentford FC
2023-12-19€30MBrentford FC
2024-05-27€28MBrentford FC
2024-10-01€25MBrentford FC
2024-12-16€22MBrentford FC
2025-03-18€18MBrentford FC
2025-05-30€10MBrentford FC
2025-10-17€15MBrentford FC
2025-12-09€16MBrentford FC
2026-06-03€16MBrentford 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
+0.370

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 46% of the 555 Premier League players.

€150k€1M€7.5M€50M€16MSee them in the Explorer →

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

Valued above 88% of the 2,065 defenders.

€20k€200k€2M€20M€16MSee them in the Explorer →

Where Hickey 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).