João
Ferreira
RBPortugal · AS Saint-Étienne
Player dossierLigue 1
JoãoFerreira
RBRight-BackDefender
- Club
- AS Saint-Étienne
- League
- Ligue 1
- Nationality
- Portugal
- Age
- 24
- Height
- 185 cm
- Foot
- Right
- Valued
- 11 Dec 2025
Ligue 1Reading the valuation
The market values Ferreira at €3M. Model A, which never saw Ferreira during training, estimates €3.7M: the market value is 20% below that estimate.
That is a factor of ×1.25. 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 €5M, 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.
- Apps
- 51
- Minutes
- 3,155
- Goals
- 0
- Assists
- 2
- Started
- 32/51
- Min / app
- 62
- Cards
- 13Y 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 Ferreira…
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 €3M
Checking APIAsking 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
Dashed ring: the defender median (50th percentile)
European club minutes
Share of minutes played in UEFA club competitions.
17% this player0% defender median80th percentile
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
- €1M
- Dec 2019
- Peak
- €4M
- Dec 2024
- Model target
- €3M
- Dec 2025
- Valuations
- 14
- 6 club changes
Dec 2025: €3M, AS Saint-Étienne. Dotted lines mark the €2M, €10M and €30M tier boundaries.
Show as a table
| Date | Market value | Club |
|---|---|---|
| 2019-12-31 | €1M | SL Benfica B |
| 2020-04-08 | €900k | SL Benfica B |
| 2020-11-02 | €800k | SL Benfica B |
| 2021-06-29 | €850k | SL Benfica B |
| 2021-12-27 | €850k | Vitória Guimarães SC |
| 2022-05-31 | €700k | Vitória Guimarães SC |
| 2022-11-01 | €400k | Rio Ave FC |
| 2023-06-01 | €400k | Watford FC |
| 2023-10-11 | €1M | Udinese Calcio |
| 2023-12-20 | €2M | Udinese Calcio |
| 2024-06-05 | €2M | Udinese Calcio |
| 2024-12-19 | €4M | SC Braga |
| 2025-05-30 | €3M | SC Braga |
| 2025-12-11 | €3M | AS Saint-Étienne |
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
- −0.221
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 →Ligue 1423 players · median €5M
Valued above 30% of the 423 Ligue 1 players.
See them in the Explorer →Defenders, all leagues2,065 players · median €2M
Valued above 59% of the 2,065 defenders.
See them in the Explorer →Where Ferreira appears
- TerminalLigue 1 in the Player Explorer
- TerminalLigue 1 on the League Landscape
Watchlists and the comparison tray are kept in this browser only.
Near this valuation closest observed values: same league, then same position
- AndréDMLOSC Lille · Ligue 1€3M
- KondogbiaDMOlympique Marseille · Ligue 1€3M
- LlorisCBLe Havre AC · Ligue 1€3M
- AjorqueCFStade Brestois 29 · Ligue 1€3M
- AlabaCBReal Madrid · defenders€3M
- VrijCBInter Milan · defenders€3M
- KeaneCBEverton FC · defenders€3M
- WeiserRBSV Werder Bremen · defenders€3M
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).