FairValue

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Valentin

Rosier

RBFrance · CA Osasuna

№ 441170Established €4M −0.28

Player dossierLaLiga

ValentinRosier

RBRight-BackDefender

Club
CA Osasuna
League
LaLiga
Nationality
France
Age
29
Height
175 cm
Foot
Right
Valued
5 Jun 2026

Reading the valuation

The market values Rosier at €3M. Model A, which never saw Rosier during training, estimates €4M: the market value is 25% below that estimate.

That is a factor of ×1.33. 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 €3.9M, 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.

▼ −0.28A €4M▼ −0.26B €3.9M
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
68
Minutes
5,470
Goals
2
Assists
3
Started
61/68
Min / app
80
Cards
13Y 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 Rosier…

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 €3M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €3MModel A €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

Valentin Rosier's percentiles among defenders: Goals per 90 51st, Assists per 90 56th, Minutes, two years 88th, Starts 68th, Minutes, last 365 days 79th, European club minutes 30th51stGoals56thAssists88thMinutes68thStarts79thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

Total club minutes in the two-year window: how much the player was used.

5,470 this player2,860 defender median88th percentile

451peer deciles · median line · this player ●9,111

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 2016
Peak
€8M
Sept 2018
Model target
€3M
Jun 2026
Valuations
30
5 club changes
Jun 2026€3MCA OsasunaValuation the model is trained to reproduce

Jun 2026: €3M, CA Osasuna. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-07-13€150kDijon FCO
2017-01-16€150kDijon FCO
2017-06-01€150kDijon FCO
2018-01-24€3MDijon FCO
2018-06-04€4.5MDijon FCO
2018-09-06€8MDijon FCO
2018-12-17€8MDijon FCO
2019-06-03€8MDijon FCO
2019-12-30€6MSporting CP
2020-04-08€4.8MSporting CP
2020-08-17€4MSporting CP
2020-12-23€4.5MBesiktas JK
2021-03-16€6MBesiktas JK
2021-05-21€7.5MBesiktas JK
2021-10-12€7.5MBesiktas JK
2022-01-04€7MBesiktas JK
2022-03-31€6.5MBesiktas JK
2022-06-01€6MBesiktas JK
2022-09-13€6.5MBesiktas JK
2022-10-27€7MBesiktas JK
2023-03-14€6.5MBesiktas JK
2023-06-08€6MBesiktas JK
2023-09-27€6MBesiktas JK
2023-12-21€5MBesiktas JK
2024-06-03€4MOGC Nice
2024-12-27€2.5MCD Leganés
2025-03-21€3MCD Leganés
2025-06-09€3MCD Leganés
2025-12-12€3MCA Osasuna
2026-06-05€3MCA Osasuna

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
−0.284

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 40% of the 509 LaLiga players.

€100k€1M€10M€100M€3MSee them in the Explorer →

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

Valued above 59% of the 2,065 defenders.

€20k€200k€2M€20M€3MSee them in the Explorer →

Where Rosier 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).