FairValue

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Junior

Firpo

LBDominican Republic · Real Betis Balompié

№ 374139Established €1.5M +0.82

Player dossierLaLiga

JuniorFirpo

LBLeft-BackDefender

Club
Real Betis Balompié
League
LaLiga
Nationality
Dominican Republic
Age
29
Height
184 cm
Foot
Left
Valued
5 Jun 2026

Reading the valuation

The market values Firpo at €3.5M. Model A, which never saw Firpo during training, estimates €1.5M: the market value is 127% above that estimate.

That is a factor of ×2.27. 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 €1.3M, 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.

▲ +0.82A €1.5M▲ +1.03B €1.3M
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
16
Minutes
1,000
Goals
0
Assists
2
Started
12/16
Min / app
63
Cards
3Y 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 Firpo…

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 €3.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €3.5MModel 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

Junior Firpo's percentiles among defenders: Goals per 90 18th, Assists per 90 93rd, Minutes, two years 12th, Starts 35th, Minutes, last 365 days 29th, European club minutes 75th18thGoals93rdAssists12thMinutes35thStarts29thRecent75thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.18 this player0.04 defender median93rd percentile

0.00peer deciles · median line · this player ●0.58

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
€100k
Aug 2017
Peak
€25M
Dec 2018
Model target
€3.5M
Jun 2026
Valuations
27
4 club changes
Jun 2026€3.5MReal Betis BalompiéValuation the model is trained to reproduce

Jun 2026: €3.5M, Real Betis Balompié. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2017-08-17€100kBetis Deportivo Balompié
2018-01-01€100kReal Betis Balompié
2018-02-18€1MReal Betis Balompié
2018-03-22€3MReal Betis Balompié
2018-05-30€5MReal Betis Balompié
2018-08-19€15MReal Betis Balompié
2018-12-21€25MReal Betis Balompié
2019-06-11€25MReal Betis Balompié
2019-12-20€25MFC Barcelona
2020-04-08€20MFC Barcelona
2020-10-08€14MFC Barcelona
2021-01-05€10MFC Barcelona
2021-06-10€8MFC Barcelona
2021-10-05€12MLeeds United
2021-12-23€12MLeeds United
2022-06-15€12MLeeds United
2022-11-03€12MLeeds United
2023-06-20€10MLeeds United
2023-10-27€7MLeeds United
2023-12-21€5MLeeds United
2024-05-24€5MLeeds United
2024-12-30€5.5MLeeds United
2025-03-28€6.5MLeeds United
2025-05-27€8MLeeds United
2025-12-12€6MReal Betis Balompié
2026-03-16€5MReal Betis Balompié
2026-06-05€3.5MReal Betis Balompié

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
+0.820

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 →

LaLiga509 players · median €4M

Valued above 47% of the 509 LaLiga players.

€100k€1M€10M€100M€3.5MSee them in the Explorer →

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

Valued above 63% of the 2,065 defenders.

€20k€200k€2M€20M€3.5MSee them in the Explorer →

Where Firpo 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).