FairValue

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

Diakhaby

CBGuinea · Valencia CF

№ 346289Emerging €1.4M +0.10

Player dossierLaLiga

MouctarDiakhaby

CBCentre-BackDefender

Club
Valencia CF
League
LaLiga
Nationality
Guinea
Age
29
Height
192 cm
Foot
Right
Valued
5 Jun 2026

Reading the valuation

The market values Diakhaby at €1.5M. Model A, which never saw Diakhaby during training, estimates €1.4M: the market value is 11% above that estimate.

That is a factor of ×1.11. 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 €907k, 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.

▲ +0.10A €1.4M▲ +0.50B €907k
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
23
Minutes
1,304
Goals
3
Assists
0
Started
16/23
Min / app
57
Cards
3Y 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 Diakhaby…

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 €1.5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1.5MModel A €1.4M

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

Mouctar Diakhaby's percentiles among defenders: Goals per 90 99th, Assists per 90 17th, Minutes, two years 18th, Starts 26th, Minutes, last 365 days 14th, European club minutes 30th99thGoals17thAssists18thMinutes26thStarts14thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Goals per 90

Club goals per 90 minutes played in the two years to the valuation date.

0.21 this player0.03 defender median99th percentile

0.00peer deciles · median line · this player ●0.41

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
€800k
Nov 2016
Peak
€30M
Sept 2019
Model target
€1.5M
Jun 2026
Valuations
34
1 club change
Jun 2026€1.5MValencia CFValuation the model is trained to reproduce

Jun 2026: €1.5M, Valencia CF. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-11-01€800kOlympique Lyon
2017-01-16€2MOlympique Lyon
2017-06-01€2.5MOlympique Lyon
2017-10-12€6MOlympique Lyon
2018-01-24€14MOlympique Lyon
2018-06-04€10MOlympique Lyon
2018-07-15€15MValencia CF
2018-12-21€12MValencia CF
2019-02-28€15MValencia CF
2019-06-11€20MValencia CF
2019-09-10€30MValencia CF
2019-12-20€30MValencia CF
2020-03-05€22MValencia CF
2020-04-08€17.5MValencia CF
2020-07-23€15MValencia CF
2020-10-08€10MValencia CF
2021-01-05€10MValencia CF
2021-03-19€10MValencia CF
2021-06-10€10MValencia CF
2021-10-13€7.5MValencia CF
2021-12-30€7.5MValencia CF
2022-06-03€7MValencia CF
2022-09-23€8MValencia CF
2022-11-07€8MValencia CF
2023-06-13€6MValencia CF
2023-12-22€6MValencia CF
2024-03-21€4MValencia CF
2024-06-07€2MValencia CF
2024-12-27€2MValencia CF
2025-06-09€2MValencia CF
2025-10-02€3MValencia CF
2025-12-12€2.8MValencia CF
2026-03-16€2MValencia CF
2026-06-05€1.5MValencia CF

Audit context group-level, not about this player

Audit group
non-UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
+0.105

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 →

LaLiga509 players · median €4M

Valued above 20% of the 509 LaLiga players.

€100k€1M€10M€100M€1.5MSee them in the Explorer →

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

Valued above 43% of the 2,065 defenders.

€20k€200k€2M€20M€1.5MSee them in the Explorer →

Where Diakhaby 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).