João
Costa
GKPortugal · FC Porto
Player dossierLiga Portugal
JoãoCosta
GKGoalkeeperGoalkeeper
- Club
- FC Porto
- League
- Liga Portugal
- Nationality
- Portugal
- Age
- 30
- Height
- 186 cm
- Foot
- Right
- Valued
- 28 May 2026
Reading the valuation
The market values Costa at €500k. Model A, which never saw Costa during training, estimates €1.6M: the market value is 68% below that estimate.
That is a factor of ×3.16. 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 €590k, closer to the market here, although it is usually further off (typical miss ×2.07).
A gap describes the model's arithmetic for this player's inputs, not what the player is worth.
- Apps
- 15
- Minutes
- 1,278
- Started
- 14/15
- Min / app
- 85
- Cards
- 0Y 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 Costa…
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 €500k
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 485 goalkeepers
Dashed ring: the goalkeeper median (50th percentile)
European club minutes
Share of minutes played in UEFA club competitions.
0% this player0% goalkeeper median32nd 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
- €50k
- Mar 2016
- Peak
- €800k
- Mar 2025
- Model target
- €500k
- May 2026
- Valuations
- 24
- 9 club changes
May 2026: €500k, FC Porto. Dotted lines mark the €2M, €10M and €30M tier boundaries.
Show as a table
| Date | Market value | Club |
|---|---|---|
| 2016-03-14 | €50k | FC Porto B |
| 2016-08-22 | €50k | FC Porto B |
| 2016-10-31 | €100k | FC Porto B |
| 2017-06-30 | €500k | FC Porto B |
| 2018-02-23 | €500k | Gil Vicente FC |
| 2018-06-29 | €300k | Gil Vicente FC |
| 2019-02-19 | €300k | FC Cartagena |
| 2019-06-29 | €300k | FC Cartagena |
| 2019-12-20 | €300k | CD Mirandés |
| 2020-10-08 | €250k | Recreativo Granada |
| 2021-01-08 | €250k | Recreativo Granada |
| 2021-06-30 | €250k | Recreativo Granada |
| 2021-10-13 | €200k | Granada CF |
| 2021-12-30 | €200k | Granada CF |
| 2022-06-03 | €200k | Granada CF |
| 2022-12-29 | €200k | Real Murcia CF |
| 2023-06-30 | €200k | Real Murcia CF |
| 2023-12-14 | €275k | CD Feirense |
| 2024-06-20 | €250k | CD Feirense |
| 2024-12-16 | €450k | CD Feirense |
| 2025-03-31 | €800k | CF Estrela Amadora |
| 2025-05-30 | €800k | CF Estrela Amadora |
| 2025-12-18 | €800k | FC Porto |
| 2026-05-28 | €500k | FC Porto |
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
- −1.150
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 20% of the 423 Liga Portugal players.
See them in the Explorer →Goalkeepers, all leagues485 players · median €1M
Valued above 27% of the 485 goalkeepers.
See them in the Explorer →Where Costa appears
Watchlists and the comparison tray are kept in this browser only.
Near this valuation closest observed values: same league, then same position
- SilvaCBFC Porto · Liga Portugal€500k
- MoutinhoCMSC Braga · Liga Portugal€500k
- JongCFFC Porto · Liga Portugal€500k
- PérezDMCasa Pia AC · Liga Portugal€500k
- GünokGKFenerbahce · goalkeepers€500k
- SteeleGKBrighton & Hove Albion · goalkeepers€500k
- DúbravkaGKBurnley FC · goalkeepers€500k
- SilvestriGKUS Cremonese · goalkeepers€500k
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).