FairValue

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

Kostenko

LMUkraine · Karpaty Lviv

№ 794617Emerging €1.2M −0.43

Player dossierPremier Liha

YanKostenko

LMLeft MidfieldMidfield

Club
Karpaty Lviv
League
Premier Liha
Nationality
Ukraine
Age
22
Height
182 cm
Foot
Right
Valued
2 Jun 2026

Reading the valuation

The market values Kostenko at €800k. Model A, which never saw Kostenko during training, estimates €1.2M: the market value is 35% below that estimate.

That is a factor of ×1.53. 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 €8.6M, 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.

▼ −0.43A €1.2M▼ −2.38B €8.6M
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
54
Minutes
3,482
Goals
6
Assists
7
Started
44/54
Min / app
64
Cards
13Y 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 Kostenko…

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 €1.2M

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

Yan Kostenko's percentiles among midfielders: Goals per 90 73rd, Assists per 90 79th, Minutes, two years 65th, Starts 73rd, Minutes, last 365 days 63rd, European club minutes 30th73rdGoals79thAssists65thMinutes73rdStarts63rdRecent30thEurope

Dashed ring: the midfielder median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.18 this player0.09 midfielder median79th percentile

0.00peer deciles · median line · this player ●0.74

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
€10k
Aug 2022
Peak
€800k
Jun 2026
Model target
€800k
Jun 2026
Valuations
9
1 club change
Jun 2026€800kKarpaty LvivValuation the model is trained to reproduce

Jun 2026: €800k, Karpaty Lviv. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2022-08-27€10kSC Poltava
2022-12-06€50kSC Poltava
2023-06-21€100kSC Poltava
2023-12-11€250kKarpaty Lviv
2024-06-06€350kKarpaty Lviv
2024-12-17€500kKarpaty Lviv
2025-06-10€600kKarpaty Lviv
2025-12-18€700kKarpaty Lviv
2026-06-02€800kKarpaty Lviv

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
−0.428

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 →

Premier Liha414 players · median €400k

Valued above 71% of the 414 Premier Liha players.

€50k€200k€1M€5M€800kSee them in the Explorer →

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

Valued above 27% of the 1,687 midfielders.

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

Where Kostenko 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).