FairValue

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Aïssa

Mandi

CBAlgeria · LOSC Lille

№ 80293Emerging €2.1M −0.76

Player dossierLigue 1

AïssaMandi

CBCentre-BackDefender

Club
LOSC Lille
League
Ligue 1
Nationality
Algeria
Age
34
Height
184 cm
Foot
Right
Valued
1 Jun 2026

Reading the valuation

The market values Mandi at €1M. Model A, which never saw Mandi during training, estimates €2.1M: the market value is 53% below that estimate.

That is a factor of ×2.14. 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 €2M, closer to the market here, although it is usually further off (typical miss ×2.07).

A gap describes the model's arithmetic for this player's inputs, not what the player is worth.

▼ −0.76A €2.1M▼ −0.67B €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
70
Minutes
5,361
Goals
1
Assists
0
Started
60/70
Min / app
77
Cards
16Y 1R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Mandi…

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 €1M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €1MModel A €2.1M

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

Aïssa Mandi's percentiles among defenders: Goals per 90 38th, Assists per 90 17th, Minutes, two years 88th, Starts 57th, Minutes, last 365 days 94th, European club minutes 87th38thGoals17thAssists88thMinutes57thStarts94thRecent87thEurope

Dashed ring: the defender median (50th percentile)

Minutes, last 365 days

Club minutes in the final year of the window: recent involvement, or the absence of it.

3,278 this player1,687 defender median94th percentile

0peer deciles · median line · this player ●4,941

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
€200k
Jul 2011
Peak
€20M
Dec 2019
Model target
€1M
Jun 2026
Valuations
39
3 club changes
Jun 2026€1MLOSC LilleValuation the model is trained to reproduce

Jun 2026: €1M, LOSC Lille. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2011-07-22€200kStade Reims
2011-12-25€400kStade Reims
2012-06-01€800kStade Reims
2012-07-25€1MStade Reims
2013-01-07€1.3MStade Reims
2013-05-30€1.5MStade Reims
2014-01-14€2MStade Reims
2014-08-07€2.5MStade Reims
2015-01-14€3MStade Reims
2015-06-06€4MStade Reims
2015-09-06€4.5MStade Reims
2016-02-04€4.5MStade Reims
2016-07-15€4.5MReal Betis Balompié
2017-01-24€5MReal Betis Balompié
2017-03-29€6MReal Betis Balompié
2017-06-05€6MReal Betis Balompié
2018-01-01€6MReal Betis Balompié
2018-03-22€8MReal Betis Balompié
2018-05-30€9MReal Betis Balompié
2018-12-21€14MReal Betis Balompié
2019-06-11€16MReal Betis Balompié
2019-12-20€20MReal Betis Balompié
2020-04-08€16MReal Betis Balompié
2020-07-23€12MReal Betis Balompié
2020-10-08€10MReal Betis Balompié
2020-11-23€8MReal Betis Balompié
2021-01-05€8MReal Betis Balompié
2021-06-10€8MReal Betis Balompié
2021-12-30€6MVillarreal CF
2022-06-03€6MVillarreal CF
2022-11-07€4MVillarreal CF
2023-06-13€3MVillarreal CF
2023-10-13€2.5MVillarreal CF
2023-12-22€2MVillarreal CF
2024-06-07€1.8MVillarreal CF
2024-12-10€1.5MLOSC Lille
2025-06-03€1.2MLOSC Lille
2025-12-15€1MLOSC Lille
2026-06-01€1MLOSC Lille

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
−0.763

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 10% of the 423 Ligue 1 players.

€100k€750k€5M€30M€1MSee them in the Explorer →

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

Valued above 35% of the 2,065 defenders.

€20k€200k€2M€20M€1MSee them in the Explorer →

Where Mandi 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).