FairValue

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Portrait of Alberto Dossena

Alberto

Dossena

CBItaly · Cagliari Calcio

№ 385394Established €3.1M +0.67

Close-up

Image: FootyLogos

Player dossierSerie A

AlbertoDossena

CBCentre-BackDefender

Club
Cagliari Calcio
League
Serie A
Nationality
Italy
Age
27
Height
195 cm
Foot
Right
Valued
29 May 2026

Reading the valuation

The market values Dossena at €6M. Model A, which never saw Dossena during training, estimates €3.1M: the market value is 96% above that estimate.

That is a factor of ×1.96. 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 €1.6M, 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.

▲ +0.67A €3.1M▲ +1.32B €1.6M
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
2,687
Goals
0
Assists
3
Started
29/35
Min / app
77
Cards
6Y 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 Dossena…

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 €6M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €6MModel A €3.1M

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 2,065 defenders

Alberto Dossena's percentiles among defenders: Goals per 90 18th, Assists per 90 77th, Minutes, two years 47th, Starts 51st, Minutes, last 365 days 24th, European club minutes 30th18thGoals77thAssists47thMinutes51stStarts24thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.10 this player0.04 defender median77th percentile

0.00peer deciles · median line · this player ●0.58

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
Nov 2015
Peak
€8M
Jun 2025
Model target
€6M
May 2026
Valuations
23
8 club changes
May 2026€6MCagliari CalcioValuation the model is trained to reproduce

May 2026: €6M, Cagliari Calcio. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2015-11-27€50kAtalanta Primavera
2016-06-08€50kAtalanta Primavera
2017-05-18€300kAC Perugia Calcio
2017-12-21€400kAC Perugia Calcio
2018-06-19€350kRobur Siena
2018-12-13€300kUS Pistoiese 1921
2019-06-19€300kUS Pistoiese 1921
2019-12-16€300kUS Alessandria Calcio 1912
2020-07-24€275kUS Alessandria Calcio 1912
2021-01-13€275kUS Avellino 1912
2021-06-23€275kUS Avellino 1912
2021-12-22€300kUS Avellino 1912
2022-06-22€300kUS Avellino 1912
2022-12-22€250kCagliari Calcio
2023-06-12€1.7MCagliari Calcio
2023-10-11€2MCagliari Calcio
2023-12-20€4MCagliari Calcio
2024-06-05€5MCagliari Calcio
2024-10-18€7MComo 1907
2024-12-18€7MComo 1907
2025-06-17€8MComo 1907
2025-12-23€7MComo 1907
2026-05-29€6MCagliari 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
+0.675

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 50% of the 507 Serie A players.

€100k€750k€5M€30M€6MSee them in the Explorer →

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

Valued above 73% of the 2,065 defenders.

€20k€200k€2M€20M€6MSee them in the Explorer →

Where Dossena 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).