FairValue

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Jacob

Ondrejka

LWSweden · Parma Calcio 1913

№ 663237Established €8M −0.37

Player dossierSerie A

JacobOndrejka

LWLeft WingerAttack

Club
Parma Calcio 1913
League
Serie A
Nationality
Sweden
Age
23
Height
179 cm
Foot
Right
Valued
29 May 2026

Reading the valuation

The market values Ondrejka at €5.5M. Model A, which never saw Ondrejka during training, estimates €8M: the market value is 31% below that estimate.

That is a factor of ×1.45. 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 €3.4M, 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.

▼ −0.37A €8M▲ +0.47B €3.4M
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
51
Minutes
2,754
Goals
12
Assists
5
Started
30/51
Min / app
54
Cards
4Y 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 Ondrejka…

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 €5.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €5.5MModel A €8M

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

Jacob Ondrejka's percentiles among attackers: Goals per 90 75th, Assists per 90 56th, Minutes, two years 62nd, Starts 50th, Minutes, last 365 days 30th, European club minutes 28th75thGoals56thAssists62ndMinutes50thStarts30thRecent28thEurope

Dashed ring: the attacker median (50th percentile)

Goals per 90

Club goals per 90 minutes played in the two years to the valuation date.

0.39 this player0.26 attacker median75th percentile

0.00peer deciles · median line · this player ●1.17

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
€200k
Aug 2020
Peak
€8M
Jun 2025
Model target
€5.5M
May 2026
Valuations
17
2 club changes
May 2026€5.5MParma Calcio 1913Valuation the model is trained to reproduce

May 2026: €5.5M, Parma Calcio 1913. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-08-05€200kIF Elfsborg
2020-12-10€500kIF Elfsborg
2021-06-09€650kIF Elfsborg
2021-12-17€650kIF Elfsborg
2022-06-24€1.2MIF Elfsborg
2022-12-14€1.2MIF Elfsborg
2023-06-27€2.5MIF Elfsborg
2023-10-23€3MRoyal Antwerp FC
2023-12-19€3MRoyal Antwerp FC
2024-03-22€4MRoyal Antwerp FC
2024-06-04€4MRoyal Antwerp FC
2024-10-02€5MRoyal Antwerp FC
2024-12-11€7MRoyal Antwerp FC
2025-06-17€8MParma Calcio 1913
2025-12-23€8MParma Calcio 1913
2026-03-24€6.5MParma Calcio 1913
2026-05-29€5.5MParma Calcio 1913

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
−0.370

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€5.5MSee them in the Explorer →

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

Valued above 68% of the 1,583 attackers.

€20k€300k€5M€75M€5.5MSee them in the Explorer →

Where Ondrejka 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).