FairValue

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Aderllan

Santos

CBBrazil · Avs Futebol

№ 159142Emerging €92k +0.08

Player dossierLiga Portugal

AderllanSantos

CBCentre-BackDefender

Club
Avs Futebol
League
Liga Portugal
Nationality
Brazil
Age
37
Height
193 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Santos at €100k. Model A, which never saw Santos during training, estimates €92k: the market value is 8% above that estimate.

That is a factor of ×1.08. 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 €198k, 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.

▲ +0.08A €92k▼ −0.68B €198k
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
45
Minutes
3,213
Goals
1
Assists
1
Started
38/45
Min / app
71
Cards
6Y 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 Santos…

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 €100k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €100kModel A €92k

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

Aderllan Santos's percentiles among defenders: Goals per 90 47th, Assists per 90 42nd, Minutes, two years 57th, Starts 54th, Minutes, last 365 days 29th, European club minutes 30th47thGoals42ndAssists57thMinutes54thStarts29thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

Total club minutes in the two-year window: how much the player was used.

3,213 this player2,860 defender median57th percentile

451peer deciles · median line · this player ●9,111

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
€150k
Apr 2011
Peak
€7.5M
Feb 2015
Model target
€100k
May 2026
Valuations
31
8 club changes
May 2026€100kAvs FutebolValuation the model is trained to reproduce

May 2026: €100k, Avs Futebol. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2011-04-07€150kCD Trofense
2012-01-09€350kCD Trofense
2013-04-20€500kSC Braga B
2013-10-08€3MSC Braga
2014-02-26€6MSC Braga
2014-07-25€6.5MSC Braga
2015-02-17€7.5MSC Braga
2015-07-01€7.5MSC Braga
2016-02-22€7MValencia CF
2016-07-15€5MValencia CF
2017-01-24€3.5MValencia CF
2017-06-05€3.5MValencia CF
2017-12-07€3MSão Paulo Futebol Clube
2018-05-23€2.5MEsporte Clube Vitória
2019-06-01€2.5MAl-Ahli SFC
2019-12-30€2.5MRio Ave FC
2020-04-08€2MRio Ave FC
2020-08-17€2.5MRio Ave FC
2021-01-28€2MRio Ave FC
2021-05-21€1.5MRio Ave FC
2021-11-05€800kRio Ave FC
2022-04-01€500kRio Ave FC
2022-06-27€350kRio Ave FC
2022-11-01€300kRio Ave FC
2023-06-16€200kRio Ave FC
2023-12-27€200kRio Ave FC
2024-06-06€200kRio Ave FC
2024-12-19€200kRio Ave FC
2025-05-30€100kAvs Futebol
2025-12-18€100kAvs Futebol
2026-05-28€100kAvs 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
+0.081

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 2% of the 423 Liga Portugal players.

€20k€200k€2M€20M€100kSee them in the Explorer →

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

Valued above 1% of the 2,065 defenders.

€20k€200k€2M€20M€100kSee them in the Explorer →

Where Santos 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).