FairValue

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

Sportiello

GKItaly · Atalanta BC

№ 199976Emerging €795k +0.01

Player dossierSerie A

MarcoSportiello

GKGoalkeeperGoalkeeper

Club
Atalanta BC
League
Serie A
Nationality
Italy
Age
34
Height
192 cm
Foot
Right
Valued
29 May 2026

Reading the valuation

The market values Sportiello at €800k. Model A, which never saw Sportiello during training, estimates €795k: the market value is 1% above that estimate.

That is a factor of ×1.01. 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 €827k, 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.

▲ +0.01A €795k▼ −0.03B €827k
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
7
Minutes
530
Started
6/7
Min / app
76
Cards
0Y 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 Sportiello…

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 €800k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €800kModel A €795k

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 485 goalkeepers

Marco Sportiello's percentiles among goalkeepers: Minutes, two years 3rd, Starts 4th, Minutes, last 365 days 14th, European club minutes 96th3rdMinutes4thStarts14thRecent96thEurope

Dashed ring: the goalkeeper median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

34% this player0% goalkeeper median96th percentile

0%peer deciles · median line · this player ●86%

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
€250k
Jul 2012
Peak
€10M
Jul 2016
Model target
€800k
May 2026
Valuations
35
7 club changes
May 2026€800kAtalanta BCValuation the model is trained to reproduce

May 2026: €800k, Atalanta BC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2012-07-09€250kAtalanta BC
2013-02-06€350kCarpi FC 1909
2013-06-19€350kCarpi FC 1909
2014-01-07€400kAtalanta BC
2014-07-01€400kAtalanta BC
2014-11-08€1.5MAtalanta BC
2015-01-07€2.5MAtalanta BC
2015-03-20€5MAtalanta BC
2015-07-01€6MAtalanta BC
2015-11-05€7.5MAtalanta BC
2016-01-04€8MAtalanta BC
2016-07-15€10MAtalanta BC
2017-01-02€9MAtalanta BC
2017-03-28€7MACF Fiorentina
2017-06-08€6MACF Fiorentina
2017-12-29€7MACF Fiorentina
2018-06-07€6MACF Fiorentina
2018-10-12€5MFrosinone Calcio
2018-12-20€5MFrosinone Calcio
2019-06-06€4MFrosinone Calcio
2019-12-12€2.5MAtalanta BC
2020-04-08€2MAtalanta BC
2020-08-25€2MAtalanta BC
2020-12-29€2MAtalanta BC
2021-06-03€2MAtalanta BC
2021-12-28€1.5MAtalanta BC
2022-06-07€1.5MAtalanta BC
2022-11-11€1.5MAtalanta BC
2023-06-15€1.5MAtalanta BC
2023-12-20€1.5MAC Milan
2024-06-05€1.5MAC Milan
2024-12-18€1.5MAC Milan
2025-06-17€1MAC Milan
2025-12-23€1MAtalanta BC
2026-05-29€800kAtalanta BC

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
+0.007

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 4% of the 507 Serie A players.

€100k€750k€5M€30M€800kSee them in the Explorer →

Goalkeepers, all leagues485 players · median €1M

Valued above 39% of the 485 goalkeepers.

€20k€200k€2M€20M€800kSee them in the Explorer →

Where Sportiello 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).