FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Boris

Popović

CBSerbia · FC Arouca

№ 470796Emerging €1.6M −0.49

Player dossierLiga Portugal

BorisPopović

CBCentre-BackDefender

Club
FC Arouca
League
Liga Portugal
Nationality
Serbia
Age
26
Height
189 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Popović at €1M. Model A, which never saw Popović during training, estimates €1.6M: the market value is 39% below that estimate.

That is a factor of ×1.63. 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 €1.7M, 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.

▼ −0.49A €1.6M▼ −0.55B €1.7M
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
39
Minutes
2,361
Goals
1
Assists
0
Started
27/39
Min / app
61
Cards
4Y 1R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Popović…

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 €1M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1MModel A €1.6M

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

Boris Popović's percentiles among defenders: Goals per 90 55th, Assists per 90 17th, Minutes, two years 41st, Starts 26th, Minutes, last 365 days 33rd, European club minutes 68th55thGoals17thAssists41stMinutes26thStarts33rdRecent68thEurope

Dashed ring: the defender median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

6% this player0% defender median68th percentile

0%peer deciles · median line · this player ●85%

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
Aug 2021
Peak
€3.5M
Jun 2024
Model target
€1M
May 2026
Valuations
14
1 club change
May 2026€1MFC AroucaValuation the model is trained to reproduce

May 2026: €1M, FC Arouca. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2021-08-03€200kCercle Brugge
2021-10-06€450kCercle Brugge
2022-01-06€400kCercle Brugge
2022-04-12€750kCercle Brugge
2022-11-04€800kCercle Brugge
2023-03-22€1.5MCercle Brugge
2023-06-09€2MCercle Brugge
2023-12-19€2MCercle Brugge
2024-03-22€3MCercle Brugge
2024-06-04€3.5MCercle Brugge
2024-12-19€2MFC Arouca
2025-05-30€1.5MFC Arouca
2025-12-18€1.2MFC Arouca
2026-05-28€1MFC Arouca

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
−0.486

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 →

Liga Portugal423 players · median €1M

Valued above 42% of the 423 Liga Portugal players.

€20k€200k€2M€20M€1MSee them in the Explorer →

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

Valued above 35% of the 2,065 defenders.

€20k€200k€2M€20M€1MSee them in the Explorer →

Where Popović 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).