FairValue

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Roberto

Fernández

LBBolivia · Akron Tolyatti

№ 598101Emerging €1.5M −0.02

Player dossierPremier Liga

RobertoFernández

LBLeft-BackDefender

Club
Akron Tolyatti
League
Premier Liga
Nationality
Bolivia
Age
26
Height
174 cm
Foot
Left
Valued
26 May 2026

Reading the valuation

The market values Fernández at €1.5M. Model A, which never saw Fernández during training, estimates €1.5M: the market value is 2% below that estimate.

That is a factor of ×1.02. 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 €1.6M, 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.

▼ −0.02A €1.5M▼ −0.06B €1.6M
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
53
Minutes
4,339
Goals
1
Assists
4
Started
48/53
Min / app
82
Cards
5Y 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 Fernández…

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 €1.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1.5MModel A €1.5M

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

Roberto Fernández's percentiles among defenders: Goals per 90 41st, Assists per 90 72nd, Minutes, two years 75th, Starts 71st, Minutes, last 365 days 76th, European club minutes 30th41stGoals72ndAssists75thMinutes71stStarts76thRecent30thEurope

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.

2,525 this player1,687 defender median76th 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
€400k
Jun 2019
Peak
€1.5M
Dec 2025
Model target
€1.5M
May 2026
Valuations
17
4 club changes
May 2026€1.5MAkron TolyattiValuation the model is trained to reproduce

May 2026: €1.5M, Akron Tolyatti. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2019-06-14€400kBlooming Santa Cruz
2019-09-10€400kCultural Leonesa
2020-03-02€400kBolívar La Paz
2020-04-08€350kBolívar La Paz
2021-03-15€450kBolívar La Paz
2021-06-11€475kBolívar La Paz
2021-10-28€625kBolívar La Paz
2022-06-10€750kBolívar La Paz
2022-11-23€950kBolívar La Paz
2023-04-10€1MBolívar La Paz
2023-07-21€1MBaltika Kaliningrad
2023-12-13€1MBaltika Kaliningrad
2024-06-04€1MBaltika Kaliningrad
2024-12-12€1MAkron Tolyatti
2025-06-04€1.2MAkron Tolyatti
2025-12-16€1.5MAkron Tolyatti
2026-05-26€1.5MAkron Tolyatti

Audit context group-level, not about this player

Audit group
non-UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
−0.025

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 Liga412 players · median €1M

Valued above 57% of the 412 Premier Liga players.

€50k€300k€2M€15M€1.5MSee them in the Explorer →

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

Valued above 43% of the 2,065 defenders.

€20k€200k€2M€20M€1.5MSee them in the Explorer →

Where Fernández 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).