FairValue

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Guilherme

Neiva

LWBrazil · Avs Futebol

№ 1065761Emerging €480k −0.47

Player dossierLiga Portugal

GuilhermeNeiva

LWLeft WingerAttack

Club
Avs Futebol
League
Liga Portugal
Nationality
Brazil
Age
25
Height
177 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Neiva at €300k. Model A, which never saw Neiva during training, estimates €480k: the market value is 37% below that estimate.

That is a factor of ×1.60. 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 €1.4M, 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.

▼ −0.47A €480k▼ −1.55B €1.4M
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
24
Minutes
923
Goals
2
Assists
3
Started
9/24
Min / app
38
Cards
2Y 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 Neiva…

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 €300k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €300kModel A €480k

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

Guilherme Neiva's percentiles among attackers: Goals per 90 35th, Assists per 90 89th, Minutes, two years 16th, Starts 18th, Minutes, last 365 days 34th, European club minutes 28th35thGoals89thAssists16thMinutes18thStarts34thRecent28thEurope

Dashed ring: the attacker median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.29 this player0.15 attacker median89th percentile

0.00peer deciles · median line · this player ●0.73

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
Sept 2025
Peak
€300k
May 2026
Model target
€300k
May 2026
Valuations
3
0 club changes
May 2026€300kAvs FutebolValuation the model is trained to reproduce

May 2026: €300k, Avs Futebol. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2025-09-30€200kAvs Futebol
2025-12-18€200kAvs Futebol
2026-05-28€300kAvs Futebol

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
−0.469

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 →

Liga Portugal423 players · median €1M

Valued above 8% of the 423 Liga Portugal players.

€20k€200k€2M€20M€300kSee them in the Explorer →

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

Valued above 8% of the 1,583 attackers.

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

Where Neiva 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).