FairValue

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Dennis

Appiah

RBFrance · AS Saint-Étienne

№ 111038Emerging €409k +0.54

Player dossierLigue 1

DennisAppiah

RBRight-BackDefender

Club
AS Saint-Étienne
League
Ligue 1
Nationality
France
Age
33
Height
179 cm
Foot
Right
Valued
11 Dec 2025

Reading the valuation

The market values Appiah at €700k. Model A, which never saw Appiah during training, estimates €409k: the market value is 71% above that estimate.

That is a factor of ×1.71. 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 €241k, 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.

▲ +0.54A €409k▲ +1.07B €241k
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
29
Minutes
2,126
Goals
0
Assists
1
Started
22/29
Min / app
73
Cards
2Y 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 Appiah…

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 €700k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €700kModel A €409k

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

Dennis Appiah's percentiles among defenders: Goals per 90 18th, Assists per 90 52nd, Minutes, two years 36th, Starts 37th, Minutes, last 365 days 34th, European club minutes 30th18thGoals52ndAssists36thMinutes37thStarts34thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.04 this player0.04 defender median52nd percentile

0.00peer deciles · median line · this player ●0.58

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
€150k
Jul 2010
Peak
€3M
Jul 2016
Model target
€700k
Dec 2025
Valuations
33
4 club changes
Dec 2025€700kAS Saint-ÉtienneValuation the model is trained to reproduce

Dec 2025: €700k, AS Saint-Étienne. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2010-07-16€150kAS Monaco
2011-05-24€150kAS Monaco
2011-09-03€400kAS Monaco
2011-12-24€500kAS Monaco
2012-05-31€500kAS Monaco
2013-01-04€500kAS Monaco
2013-05-29€500kAS Monaco
2014-01-13€800kSM Caen
2014-08-03€1.5MSM Caen
2015-01-14€1.5MSM Caen
2015-06-06€2MSM Caen
2016-02-04€2.5MSM Caen
2016-07-15€3MRSC Anderlecht
2017-01-21€3MRSC Anderlecht
2017-06-06€3MRSC Anderlecht
2018-01-09€2.5MRSC Anderlecht
2018-06-03€2.5MRSC Anderlecht
2018-12-27€1.5MRSC Anderlecht
2019-06-10€1.5MRSC Anderlecht
2019-12-19€1.8MFC Nantes
2020-04-08€1.4MFC Nantes
2020-10-15€1.8MFC Nantes
2021-06-04€1.8MFC Nantes
2021-12-16€1.5MFC Nantes
2022-05-30€2MFC Nantes
2022-11-02€1.5MFC Nantes
2023-06-16€1.5MAS Saint-Étienne
2023-10-27€1MAS Saint-Étienne
2023-12-13€1MAS Saint-Étienne
2024-06-11€1MAS Saint-Étienne
2024-12-10€900kAS Saint-Étienne
2025-06-03€800kAS Saint-Étienne
2025-12-11€700kAS 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
+0.536

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 5% of the 423 Ligue 1 players.

€100k€750k€5M€30M€700kSee them in the Explorer →

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

Valued above 26% of the 2,065 defenders.

€20k€200k€2M€20M€700kSee them in the Explorer →

Where Appiah 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).