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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  • TerminalComparison StudioTwo to four players on one scale.
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  • TerminalMarket LandscapeHow observed value is distributed, and where the model drifts.

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Adam

Forrester

RBScotland · St. Johnstone FC

№ 1026007Emerging €169k +0.39

Player dossierPremiership

AdamForrester

RBRight-BackDefender

Club
St. Johnstone FC
League
Premiership
Nationality
Scotland
Age
21
Height
175 cm
Foot
Right
Valued
21 May 2026

Reading the valuation

The market values Forrester at €250k. Model A, which never saw Forrester during training, estimates €169k: the market value is 48% above that estimate.

That is a factor of ×1.48. 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 €764k, 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.

▲ +0.39A €169k▼ −1.12B €764k
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
25
Minutes
1,652
Goals
0
Assists
1
Started
18/25
Min / app
66
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 Forrester…

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 €250k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €250kModel A €169k

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

Adam Forrester's percentiles among defenders: Goals per 90 18th, Assists per 90 60th, Minutes, two years 26th, Starts 30th, Minutes, last 365 days 2nd, European club minutes 30th18thGoals60thAssists26thMinutes30thStarts2ndRecent30thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.05 this player0.04 defender median60th 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
€200k
Dec 2024
Peak
€400k
Jun 2025
Model target
€250k
May 2026
Valuations
5
1 club change
May 2026€250kSt. Johnstone FCValuation the model is trained to reproduce

May 2026: €250k, St. Johnstone FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2024-12-03€200kHeart of Midlothian FC
2025-03-12€250kHeart of Midlothian FC
2025-06-17€400kHeart of Midlothian FC
2025-12-10€250kSt. Johnstone FC
2026-05-21€250kSt. Johnstone 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
+0.390

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 32% of the 311 Premiership players.

€20k€150k€1M€7.5M€250kSee them in the Explorer →

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

Valued above 7% of the 2,065 defenders.

€20k€200k€2M€20M€250kSee them in the Explorer →

Where Forrester 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).