FairValue

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João

Afonso

CBPortugal · CD Tondela

№ 211107Emerging €74k −0.40

Player dossierLiga Portugal

JoãoAfonso

CBCentre-BackDefender

Club
CD Tondela
League
Liga Portugal
Nationality
Portugal
Age
36
Height
188 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Afonso at €50k. Model A, which never saw Afonso during training, estimates €74k: the market value is 33% below that estimate.

That is a factor of ×1.49. 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 €167k, 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.

▼ −0.40A €74k▼ −1.21B €167k
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
14
Minutes
698
Goals
0
Assists
0
Started
7/14
Min / app
50
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 Afonso…

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 €50k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €50kModel A €74k

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

João Afonso's percentiles among defenders: Goals per 90 18th, Assists per 90 17th, Minutes, two years 5th, Starts 8th, Minutes, last 365 days 18th, European club minutes 30th18thGoals17thAssists5thMinutes8thStarts18thRecent30thEurope

Dashed ring: the defender median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

0% this player0% defender median30th percentile

0%peer deciles · median line · this player ●85%

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
Jul 2014
Peak
€2.2M
Jul 2015
Model target
€50k
May 2026
Valuations
27
6 club changes
May 2026€50kCD TondelaValuation the model is trained to reproduce

May 2026: €50k, CD Tondela. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2014-07-25€100kVitória Guimarães SC
2015-02-17€1.5MVitória Guimarães SC
2015-07-01€2.2MVitória Guimarães SC
2016-02-24€2MVitória Guimarães SC
2016-07-29€1.5MVitória Guimarães SC
2017-02-22€1.5MGD Estoril Praia
2017-06-26€1.5MGD Estoril Praia
2018-01-01€1MCórdoba CF
2018-06-13€1MVitória Guimarães SC
2019-01-11€800kVitória Guimarães SC
2019-06-07€700kVitória Guimarães SC
2019-10-11€850kCD Santa Clara
2019-12-30€1MCD Santa Clara
2020-04-08€800kCD Santa Clara
2020-08-17€1MCD Santa Clara
2021-01-28€800kCD Santa Clara
2021-05-21€500kCD Santa Clara
2021-12-27€450kCD Santa Clara
2022-05-31€300kCD Santa Clara
2022-12-28€125kSC União Torreense
2023-06-28€100kSC União Torreense
2023-12-14€100kSC União Torreense
2024-06-20€100kSC União Torreense
2024-12-16€100kCD Tondela
2025-06-23€75kCD Tondela
2025-12-18€50kCD Tondela
2026-05-28€50kCD Tondela

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
−0.398

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 0% of the 423 Liga Portugal players.

€20k€200k€2M€20M€50kSee them in the Explorer →

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

Valued above 0% of the 2,065 defenders.

€20k€200k€2M€20M€50kSee them in the Explorer →

Where Afonso 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).