FairValue

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Alessandro

Deiola

CMItaly · Cagliari Calcio

№ 235931Emerging €2.1M −0.34

Player dossierSerie A

AlessandroDeiola

CMCentral MidfieldMidfield

Club
Cagliari Calcio
League
Serie A
Nationality
Italy
Age
30
Height
190 cm
Foot
Right
Valued
29 May 2026

Reading the valuation

The market values Deiola at €1.5M. Model A, which never saw Deiola during training, estimates €2.1M: the market value is 29% below that estimate.

That is a factor of ×1.41. 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 €1.7M, 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.

▼ −0.34A €2.1M▼ −0.10B €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
55
Minutes
3,225
Goals
2
Assists
3
Started
37/55
Min / app
59
Cards
10Y 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 Deiola…

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 €1.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1.5MModel A €2.1M

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

Alessandro Deiola's percentiles among midfielders: Goals per 90 37th, Assists per 90 46th, Minutes, two years 61st, Starts 46th, Minutes, last 365 days 54th, European club minutes 30th37thGoals46thAssists61stMinutes46thStarts54thRecent30thEurope

Dashed ring: the midfielder median (50th percentile)

Minutes, two years

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

3,225 this player2,607 midfielder median61st percentile

451peer deciles · median line · this player ●9,624

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
€50k
Oct 2012
Peak
€2M
Oct 2021
Model target
€1.5M
May 2026
Valuations
29
9 club changes
May 2026€1.5MCagliari CalcioValuation the model is trained to reproduce

May 2026: €1.5M, Cagliari Calcio. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2012-10-23€50kCagliari Primavera
2013-04-10€50kCagliari Primavera
2014-05-08€75kCagliari Primavera
2015-01-21€125kAC Tuttocuoio
2015-06-22€175kAC Tuttocuoio
2015-12-28€200kCagliari Calcio
2016-06-13€1.6MCagliari Calcio
2016-12-19€1.5MSpezia Calcio
2017-06-08€1.5MCagliari Calcio
2017-12-29€1.3MCagliari Calcio
2018-06-07€1.3MCagliari Calcio
2018-12-20€1.2MParma Calcio 1913
2019-06-06€1.2MCagliari Calcio
2019-12-12€1.2MCagliari Calcio
2020-04-08€950kUS Lecce
2020-08-25€1MUS Lecce
2020-12-29€1MSpezia Calcio
2021-06-03€1MCagliari Calcio
2021-10-14€2MCagliari Calcio
2021-12-28€2MCagliari Calcio
2022-06-07€2MCagliari Calcio
2022-12-22€1.8MCagliari Calcio
2023-06-12€1.8MCagliari Calcio
2023-12-20€1.6MCagliari Calcio
2024-06-05€1.9MCagliari Calcio
2024-12-18€1.6MCagliari Calcio
2025-06-17€1.6MCagliari Calcio
2025-12-23€1.6MCagliari Calcio
2026-05-29€1.5MCagliari 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
−0.340

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 15% of the 507 Serie A players.

€100k€750k€5M€30M€1.5MSee them in the Explorer →

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

Valued above 39% of the 1,687 midfielders.

€20k€200k€2M€20M€1.5MSee them in the Explorer →

Where Deiola 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).