FairValue

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  • EnvironmentOverviewWhat FairValue measures, what it found, where to go next.
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Joan

Sastre

RBSpain · PAOK Thessaloniki

№ 350364Emerging €2M −0.92

Player dossierSuper League

JoanSastre

RBRight-BackDefender

Club
PAOK Thessaloniki
League
Super League
Nationality
Spain
Age
29
Height
174 cm
Foot
Right
Valued
4 Jun 2026

Reading the valuation

The market values Sastre at €800k. Model A, which never saw Sastre during training, estimates €2M: the market value is 60% below that estimate.

That is a factor of ×2.52. 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 €2.3M, 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.

▼ −0.92A €2M▼ −1.04B €2.3M
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
37
Minutes
2,596
Goals
1
Assists
3
Started
29/37
Min / app
70
Cards
5Y 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 Sastre…

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 €800k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €800kModel A €2M

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

Joan Sastre's percentiles among defenders: Goals per 90 53rd, Assists per 90 78th, Minutes, two years 45th, Starts 41st, Minutes, last 365 days 22nd, European club minutes 87th53rdGoals78thAssists45thMinutes41stStarts22ndRecent87thEurope

Dashed ring: the defender median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

22% this player0% defender median87th 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
€50k
Aug 2016
Peak
€2M
Jun 2019
Model target
€800k
Jun 2026
Valuations
24
2 club changes
Jun 2026€800kPAOK ThessalonikiValuation the model is trained to reproduce

Jun 2026: €800k, PAOK Thessaloniki. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-08-01€50kRCD Mallorca B
2016-10-27€100kRCD Mallorca B
2017-02-02€200kRCD Mallorca B
2017-06-05€200kRCD Mallorca B
2018-01-01€800kRCD Mallorca
2018-05-30€1MRCD Mallorca
2019-02-19€1MRCD Mallorca
2019-06-29€2MRCD Mallorca
2019-12-20€2MRCD Mallorca
2020-04-08€1.6MRCD Mallorca
2020-10-08€1.6MRCD Mallorca
2021-01-08€1.6MRCD Mallorca
2021-06-24€2MRCD Mallorca
2021-12-30€1.6MRCD Mallorca
2022-06-09€1.8MPAOK Thessaloniki
2022-11-07€1.5MPAOK Thessaloniki
2023-05-22€1.5MPAOK Thessaloniki
2023-12-20€1.2MPAOK Thessaloniki
2024-05-30€1.5MPAOK Thessaloniki
2024-12-18€1.3MPAOK Thessaloniki
2025-05-23€1.3MPAOK Thessaloniki
2025-12-12€1MPAOK Thessaloniki
2026-03-06€900kPAOK Thessaloniki
2026-06-04€800kPAOK Thessaloniki

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
−0.923

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 →

Super League356 players · median €600k

Valued above 60% of the 356 Super League players.

€20k€150k€1M€7.5M€800kSee them in the Explorer →

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

Valued above 29% of the 2,065 defenders.

€20k€200k€2M€20M€800kSee them in the Explorer →

Where Sastre 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).