FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Portrait of Reda Belahyane

Reda

Belahyane

DMMorocco · SS Lazio

№ 982855Established €3.4M +0.70

Close-up

Image: FootyLogos

Player dossierSerie A

RedaBelahyane

DMDefensive MidfieldMidfield

Club
SS Lazio
League
Serie A
Nationality
Morocco
Age
21
Height
173 cm
Foot
Right
Valued
29 May 2026

Reading the valuation

The market values Belahyane at €6.8M. Model A, which never saw Belahyane during training, estimates €3.4M: the market value is 102% above that estimate.

That is a factor of ×2.02. 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 €1.2M, 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.

▲ +0.70A €3.4M▲ +1.75B €1.2M
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
42
Minutes
2,463
Goals
0
Assists
4
Started
23/42
Min / app
59
Cards
7Y 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 Belahyane…

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 €6.8M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €6.8MModel A €3.4M

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 1,687 midfielders

Reda Belahyane's percentiles among midfielders: Goals per 90 10th, Assists per 90 70th, Minutes, two years 47th, Starts 28th, Minutes, last 365 days 16th, European club minutes 30th10thGoals70thAssists47thMinutes28thStarts16thRecent30thEurope

Dashed ring: the midfielder median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.15 this player0.09 midfielder median70th percentile

0.00peer deciles · median line · this player ●0.74

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
Sept 2022
Peak
€10M
Dec 2024
Model target
€6.8M
May 2026
Valuations
11
3 club changes
May 2026€6.8MSS LazioValuation the model is trained to reproduce

May 2026: €6.8M, SS Lazio. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2022-09-19€150kOGC Nice B
2022-11-02€150kOGC Nice B
2023-06-27€300kOGC Nice
2023-12-18€200kOGC Nice
2024-03-12€500kHellas Verona
2024-06-05€500kHellas Verona
2024-10-18€5MHellas Verona
2024-12-18€10MHellas Verona
2025-06-17€10MSS Lazio
2025-12-23€8.5MSS Lazio
2026-05-29€6.8MSS Lazio

Audit context group-level, not about this player

Audit group
non-UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
+0.703

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 →

Serie A507 players · median €5.5M

Valued above 55% of the 507 Serie A players.

€100k€750k€5M€30M€6.8MSee them in the Explorer →

Midfielders, all leagues1,687 players · median €2M

Valued above 71% of the 1,687 midfielders.

€20k€200k€2M€20M€6.8MSee them in the Explorer →

Where Belahyane 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).