FairValue

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

Lahssaini

CMBelgium · RAAL La Louvière

№ 535706Emerging €1.2M −0.52

Player dossierPro League

SamiLahssaini

CMCentral MidfieldMidfield

Club
RAAL La Louvière
League
Pro League
Nationality
Belgium
Age
27
Height
177 cm
Foot
Right
Valued
4 Jun 2026

Reading the valuation

The market values Lahssaini at €700k. Model A, which never saw Lahssaini during training, estimates €1.2M: the market value is 40% below that estimate.

That is a factor of ×1.68. 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 €1M, closer to the market here, although it is usually further off (typical miss ×2.07).

A gap describes the model's arithmetic for this player's inputs, not what the player is worth.

▼ −0.52A €1.2M▼ −0.39B €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
32
Minutes
2,770
Goals
1
Assists
1
Started
31/32
Min / app
87
Cards
4Y 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 Lahssaini…

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 €700k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €700kModel A €1.2M

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

Sami Lahssaini's percentiles among midfielders: Goals per 90 25th, Assists per 90 21st, Minutes, two years 53rd, Starts 96th, Minutes, last 365 days 86th, European club minutes 30th25thGoals21stAssists53rdMinutes96thStarts86thRecent30thEurope

Dashed ring: the midfielder median (50th percentile)

Starts

Share of appearances started rather than entered from the bench.

97% this player69% midfielder median96th percentile

7%peer deciles · median line · this player ●100%

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
Jul 2019
Peak
€700k
Jun 2026
Model target
€700k
Jun 2026
Valuations
16
3 club changes
Jun 2026€700kRAAL La LouvièreValuation the model is trained to reproduce

Jun 2026: €700k, RAAL La Louvière. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2019-07-25€150kFC Metz
2019-12-19€150kFC Metz
2020-08-20€150kRFC Seraing
2020-10-21€250kRFC Seraing
2021-02-23€400kRFC Seraing
2021-10-06€400kRFC Seraing
2022-01-06€450kRFC Seraing
2022-04-12€500kRFC Seraing
2022-11-04€600kRFC Seraing
2023-06-09€450kRFC Seraing
2023-12-18€400kFC Metz
2024-12-20€350kRAAL La Louvière
2025-04-24€450kRAAL La Louvière
2025-10-01€600kRAAL La Louvière
2025-12-10€600kRAAL La Louvière
2026-06-04€700kRAAL La Louvière

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
−0.518

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 →

Pro League350 players · median €1.8M

Valued above 19% of the 350 Pro League players.

€100k€750k€5M€30M€700kSee them in the Explorer →

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

Valued above 23% of the 1,687 midfielders.

€20k€200k€2M€20M€700kSee them in the Explorer →

Where Lahssaini 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).