FairValue

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Konstantinos

Tsimikas

LBGreece · AS Roma

№ 338070Established €3.3M +0.31

Player dossierSerie A

KonstantinosTsimikas

LBLeft-BackDefender

Club
AS Roma
League
Serie A
Nationality
Greece
Age
30
Height
179 cm
Foot
Left
Valued
29 May 2026

Reading the valuation

The market values Tsimikas at €4.5M. Model A, which never saw Tsimikas during training, estimates €3.3M: the market value is 36% above that estimate.

That is a factor of ×1.36. 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 €2.2M, 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.

▲ +0.31A €3.3M▲ +0.72B €2.2M
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
51
Minutes
2,507
Goals
0
Assists
3
Started
27/51
Min / app
49
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 Tsimikas…

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 €4.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €4.5MModel A €3.3M

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

Konstantinos Tsimikas's percentiles among defenders: Goals per 90 18th, Assists per 90 79th, Minutes, two years 43rd, Starts 9th, Minutes, last 365 days 30th, European club minutes 97th18thGoals79thAssists43rdMinutes9thStarts30thRecent97thEurope

Dashed ring: the defender median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

34% this player0% defender median97th 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
Nov 2014
Peak
€22M
Dec 2023
Model target
€4.5M
May 2026
Valuations
30
6 club changes
May 2026€4.5MAS RomaValuation the model is trained to reproduce

May 2026: €4.5M, AS Roma. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2014-11-11€100kOlympiacos Piraeus U20
2015-09-27€200kOlympiacos Piraeus
2016-06-21€250kOlympiacos Piraeus
2016-12-21€250kOlympiacos Piraeus
2017-03-27€300kEsbjerg fB
2017-06-21€300kEsbjerg fB
2017-10-26€500kWillem II Tilburg
2018-01-17€750kWillem II Tilburg
2018-06-12€850kWillem II Tilburg
2018-12-07€1.8MOlympiacos Piraeus
2019-05-21€2MOlympiacos Piraeus
2019-09-23€3.5MOlympiacos Piraeus
2019-12-18€4.5MOlympiacos Piraeus
2020-04-08€3.5MOlympiacos Piraeus
2020-08-04€9MOlympiacos Piraeus
2020-10-13€9MLiverpool FC
2021-03-18€8MLiverpool FC
2021-06-08€8MLiverpool FC
2021-10-05€10MLiverpool FC
2021-12-23€10MLiverpool FC
2022-06-15€15MLiverpool FC
2022-11-03€18MLiverpool FC
2023-06-20€18MLiverpool FC
2023-12-19€22MLiverpool FC
2024-05-27€22MLiverpool FC
2024-12-16€20MLiverpool FC
2025-05-30€18MLiverpool FC
2025-12-23€10MAS Roma
2026-03-24€8MAS Roma
2026-05-29€4.5MAS Roma

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
+0.311

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 →

Serie A507 players · median €5.5M

Valued above 42% of the 507 Serie A players.

€100k€750k€5M€30M€4.5MSee them in the Explorer →

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

Valued above 69% of the 2,065 defenders.

€20k€200k€2M€20M€4.5MSee them in the Explorer →

Where Tsimikas 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).