FairValue

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Mehdi

Léris

RWAlgeria · Pisa Sporting Club

№ 348601Emerging €2.8M −0.44

Player dossierSerie A

MehdiLéris

RWRight WingerAttack

Club
Pisa Sporting Club
League
Serie A
Nationality
Algeria
Age
28
Height
186 cm
Foot
Right
Valued
29 May 2026

Reading the valuation

The market values Léris at €1.8M. Model A, which never saw Léris during training, estimates €2.8M: the market value is 35% below that estimate.

That is a factor of ×1.55. 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 €1.9M, 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.

▼ −0.44A €2.8M▼ −0.08B €1.9M
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
35
Minutes
1,913
Goals
2
Assists
3
Started
21/35
Min / app
55
Cards
2Y 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 Léris…

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 €1.8M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1.8MModel A €2.8M

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 1,583 attackers

Mehdi Léris's percentiles among attackers: Goals per 90 13th, Assists per 90 48th, Minutes, two years 42nd, Starts 52nd, Minutes, last 365 days 71st, European club minutes 28th13thGoals48thAssists42ndMinutes52ndStarts71stRecent28thEurope

Dashed ring: the attacker median (50th percentile)

Minutes, last 365 days

Club minutes in the final year of the window: recent involvement, or the absence of it.

1,913 this player1,301 attacker median71st percentile

0peer deciles · median line · this player ●4,703

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
€125k
Nov 2015
Peak
€2.5M
Jun 2019
Model target
€1.8M
May 2026
Valuations
24
7 club changes
May 2026€1.8MPisa Sporting ClubValuation the model is trained to reproduce

May 2026: €1.8M, Pisa Sporting Club. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2015-11-27€125kChievo Primavera
2016-06-08€300kChievo Primavera
2017-06-26€300kJuventus Primavera
2017-12-29€300kChievo Verona
2018-06-07€300kChievo Verona
2018-12-20€800kChievo Verona
2019-03-01€2MChievo Verona
2019-06-06€2.5MChievo Verona
2019-12-12€2.5MUC Sampdoria
2020-04-08€2.3MUC Sampdoria
2020-08-25€2.3MUC Sampdoria
2020-12-29€2MUC Sampdoria
2021-06-03€1.5MUC Sampdoria
2021-10-14€2.2MBrescia Calcio (- 2025)
2021-12-29€2MBrescia Calcio (- 2025)
2022-06-06€2.4MBrescia Calcio (- 2025)
2022-11-11€2.2MUC Sampdoria
2023-06-15€2.5MUC Sampdoria
2023-12-21€2.5MStoke City
2024-05-24€2.5MStoke City
2024-12-23€2.5MPisa Sporting Club
2025-06-02€2.2MPisa Sporting Club
2025-12-23€2MPisa Sporting Club
2026-05-29€1.8MPisa Sporting Club

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
−0.437

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 18% of the 507 Serie A players.

€100k€750k€5M€30M€1.8MSee them in the Explorer →

Attackers, all leagues1,583 players · median €2.5M

Valued above 43% of the 1,583 attackers.

€20k€300k€5M€75M€1.8MSee them in the Explorer →

Where Léris 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).