FairValue

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Gabriele

Zappa

RBItaly · Cagliari Calcio

№ 392569Established €4.4M −0.39

Player dossierSerie A

GabrieleZappa

RBRight-BackDefender

Club
Cagliari Calcio
League
Serie A
Nationality
Italy
Age
26
Height
187 cm
Foot
Right
Valued
29 May 2026

Reading the valuation

The market values Zappa at €3M. Model A, which never saw Zappa during training, estimates €4.4M: the market value is 32% below 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 €5.3M, 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 €4.4M▼ −0.57B €5.3M
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
73
Minutes
4,976
Goals
2
Assists
3
Started
57/73
Min / app
68
Cards
7Y 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 Zappa…

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 €3M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €3MModel A €4.4M

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 2,065 defenders

Gabriele Zappa's percentiles among defenders: Goals per 90 53rd, Assists per 90 59th, Minutes, two years 83rd, Starts 41st, Minutes, last 365 days 50th, European club minutes 30th53rdGoals59thAssists83rdMinutes41stStarts50thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

Total club minutes in the two-year window: how much the player was used.

4,976 this player2,860 defender median83rd percentile

451peer deciles · median line · this player ●9,111

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
€75k
Jun 2018
Peak
€7M
Dec 2020
Model target
€3M
May 2026
Valuations
21
2 club changes
May 2026€3MCagliari CalcioValuation the model is trained to reproduce

May 2026: €3M, Cagliari Calcio. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2018-06-30€75kInter Milan Primavera
2019-06-17€500kInter Milan Primavera
2019-12-30€500kDelfino Pescara 1936
2020-04-08€450kDelfino Pescara 1936
2020-08-21€2.5MDelfino Pescara 1936
2020-12-29€7MCagliari Calcio
2021-06-03€7MCagliari Calcio
2021-12-28€6MCagliari Calcio
2022-03-15€5MCagliari Calcio
2022-06-07€3.8MCagliari Calcio
2022-12-22€2.5MCagliari Calcio
2023-03-20€2MCagliari Calcio
2023-06-12€2MCagliari Calcio
2023-12-20€2MCagliari Calcio
2024-06-05€2.5MCagliari Calcio
2024-12-18€3.5MCagliari Calcio
2025-03-25€4MCagliari Calcio
2025-06-17€4MCagliari Calcio
2025-12-23€4MCagliari Calcio
2026-03-24€3.5MCagliari Calcio
2026-05-29€3MCagliari Calcio

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
−0.389

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 29% of the 507 Serie A players.

€100k€750k€5M€30M€3MSee them in the Explorer →

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

Valued above 59% of the 2,065 defenders.

€20k€200k€2M€20M€3MSee them in the Explorer →

Where Zappa 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).