FairValue

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

Lyakh

LBUkraine · Karpaty Lviv

№ 533537Emerging €836k −0.18

Player dossierPremier Liha

RostyslavLyakh

LBLeft-BackDefender

Club
Karpaty Lviv
League
Premier Liha
Nationality
Ukraine
Age
25
Height
178 cm
Foot
Both
Valued
2 Jun 2026

Reading the valuation

The market values Lyakh at €700k. Model A, which never saw Lyakh during training, estimates €836k: the market value is 16% below that estimate.

That is a factor of ×1.19. 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 €6.8M, 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.

▼ −0.18A €836k▼ −2.27B €6.8M
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
49
Minutes
3,847
Goals
2
Assists
3
Started
42/49
Min / app
79
Cards
9Y 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 Lyakh…

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 €700k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €700kModel A €836k

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

Rostyslav Lyakh's percentiles among defenders: Goals per 90 61st, Assists per 90 67th, Minutes, two years 67th, Starts 57th, Minutes, last 365 days 83rd, European club minutes 30th61stGoals67thAssists67thMinutes57thStarts83rdRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, last 365 days

Club minutes in the final year of the window: recent involvement, or the absence of it.

2,774 this player1,687 defender median83rd percentile

0peer deciles · median line · this player ●4,941

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
Jan 2020
Peak
€700k
Jun 2026
Model target
€700k
Jun 2026
Valuations
13
3 club changes
Jun 2026€700kKarpaty LvivValuation the model is trained to reproduce

Jun 2026: €700k, Karpaty Lviv. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-01-08€200kKarpaty Lviv
2021-01-14€150kRukh Lviv II
2021-06-07€100kRukh Lviv II
2021-12-20€200kRukh Lviv
2022-05-18€200kRukh Lviv
2022-12-06€400kRukh Lviv
2023-06-21€500kRukh Lviv
2023-12-11€400kRukh Lviv
2024-06-06€400kRukh Lviv
2024-12-17€400kRukh Lviv
2025-06-10€500kRukh Lviv
2025-12-18€600kRukh Lviv
2026-06-02€700kKarpaty 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
−0.177

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 67% of the 414 Premier Liha players.

€50k€200k€1M€5M€700kSee them in the Explorer →

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

Valued above 26% of the 2,065 defenders.

€20k€200k€2M€20M€700kSee them in the Explorer →

Where Lyakh 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).