FairValue

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Portrait of Gustav Isaksen

Gustav

Isaksen

RWDenmark · SS Lazio

№ 462823Elite €15.7M −0.05

Close-up

Image: FootyLogos

Player dossierSerie A

GustavIsaksen

RWRight WingerAttack

Club
SS Lazio
League
Serie A
Nationality
Denmark
Age
25
Height
181 cm
Foot
Left
Valued
29 May 2026

Reading the valuation

The market values Isaksen at €15M. Model A, which never saw Isaksen during training, estimates €15.7M: the market value is 5% below that estimate.

That is a factor of ×1.05. 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 €11.3M, 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.

▼ −0.05A €15.7M▲ +0.29B €11.3M
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
83
Minutes
4,750
Goals
11
Assists
7
Started
56/83
Min / app
57
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 Isaksen…

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 €15M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €15MModel A €15.7M

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

Gustav Isaksen's percentiles among attackers: Goals per 90 38th, Assists per 90 44th, Minutes, two years 89th, Starts 64th, Minutes, last 365 days 69th, European club minutes 72nd38thGoals44thAssists89thMinutes64thStarts69thRecent72ndEurope

Dashed ring: the attacker median (50th percentile)

Minutes, two years

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

4,750 this player2,242 attacker median89th percentile

450peer deciles · median line · this player ●8,788

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
Dec 2018
Peak
€20M
Mar 2025
Model target
€15M
May 2026
Valuations
20
2 club changes
May 2026€15MSS LazioValuation the model is trained to reproduce

May 2026: €15M, SS Lazio. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2018-12-21€50kFC Midtjylland U19
2019-09-09€100kFC Midtjylland
2019-12-22€350kFC Midtjylland
2020-04-08€325kFC Midtjylland
2020-07-31€350kFC Midtjylland
2020-12-23€400kFC Midtjylland
2021-06-04€1MFC Midtjylland
2021-10-06€3MFC Midtjylland
2021-12-28€3.5MFC Midtjylland
2022-06-20€4.5MFC Midtjylland
2022-12-22€5MFC Midtjylland
2023-06-26€7.5MFC Midtjylland
2023-10-11€12MSS Lazio
2023-12-20€12MSS Lazio
2024-06-05€12MSS Lazio
2024-12-18€15MSS Lazio
2025-03-25€20MSS Lazio
2025-06-17€20MSS Lazio
2025-12-23€17MSS Lazio
2026-05-29€15MSS Lazio

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
−0.047

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 75% of the 507 Serie A players.

€100k€750k€5M€30M€15MSee them in the Explorer →

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

Valued above 81% of the 1,583 attackers.

€20k€300k€5M€75M€15MSee them in the Explorer →

Where Isaksen 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).