FairValue

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Rubén

Pérez

DMSpain · AE Kifisia

№ 113045Emerging €128k −0.02

Player dossierSuper League

RubénPérez

DMDefensive MidfieldMidfield

Club
AE Kifisia
League
Super League
Nationality
Spain
Age
37
Height
178 cm
Foot
Right
Valued
4 Jun 2026

Reading the valuation

The market values Pérez at €125k. Model A, which never saw Pérez during training, estimates €128k: the market value is 2% below that estimate.

That is a factor of ×1.02. 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 €132k, 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.

▼ −0.02A €128k▼ −0.05B €132k
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
24
Minutes
1,514
Goals
0
Assists
0
Started
19/24
Min / app
63
Cards
9Y 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 Pérez…

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 €125k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €125kModel A €128k

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 1,687 midfielders

Rubén Pérez's percentiles among midfielders: Goals per 90 10th, Assists per 90 8th, Minutes, two years 25th, Starts 69th, Minutes, last 365 days 49th, European club minutes 30th10thGoals8thAssists25thMinutes69thStarts49thRecent30thEurope

Dashed ring: the midfielder median (50th percentile)

Starts

Share of appearances started rather than entered from the bench.

79% this player69% midfielder median69th percentile

7%peer deciles · median line · this player ●100%

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
€1.2M
Aug 2010
Peak
€7.5M
May 2018
Model target
€125k
Jun 2026
Valuations
43
10 club changes
Jun 2026€125kAE KifisiaValuation the model is trained to reproduce

Jun 2026: €125k, AE Kifisia. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2010-08-15€1.2MDeportivo de La Coruña
2010-10-22€1MDeportivo de La Coruña
2010-12-10€1.5MDeportivo de La Coruña
2010-12-28€2.5MDeportivo de La Coruña
2011-02-04€2.5MDeportivo de La Coruña
2011-08-12€3MGetafe CF
2012-02-05€2.8MGetafe CF
2012-08-19€3MReal Betis Balompié
2013-01-11€3MReal Betis Balompié
2013-06-13€3MReal Betis Balompié
2013-07-25€2.5MElche CF
2014-01-23€3MElche CF
2014-07-22€3.5MTorino FC
2015-01-07€2.8MTorino FC
2015-01-23€2.5MGranada CF
2015-07-01€2.5MAtlético de Madrid
2016-02-22€2.5MGranada CF
2016-07-15€2.5MGranada CF
2017-01-24€2.5MCD Leganés
2017-06-05€2.5MCD Leganés
2018-01-01€5MCD Leganés
2018-05-30€7.5MCD Leganés
2018-12-21€7.5MCD Leganés
2019-06-11€7.5MCD Leganés
2019-12-20€7.5MCD Leganés
2020-04-08€6MCD Leganés
2020-10-08€3.5MCD Leganés
2021-01-08€3MCD Leganés
2021-03-19€2.5MCD Leganés
2021-06-24€2MCD Leganés
2021-11-01€1.5MPanathinaikos
2022-06-09€1MPanathinaikos
2022-11-07€1MPanathinaikos
2023-05-22€1MPanathinaikos
2023-09-21€800kPanathinaikos
2023-12-20€800kPanathinaikos
2024-05-30€600kPanathinaikos
2024-09-26€500kPanathinaikos
2024-12-18€350kPanathinaikos
2025-03-14€300kPanathinaikos
2025-05-23€200kPanathinaikos
2025-12-12€175kAE Kifisia
2026-06-04€125kAE Kifisia

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
−0.023

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 3% of the 356 Super League players.

€20k€150k€1M€7.5M€125kSee them in the Explorer →

Midfielders, all leagues1,687 players · median €2M

Valued above 2% of the 1,687 midfielders.

€20k€200k€2M€20M€125kSee them in the Explorer →

Where Pérez 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).