FairValue

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Calvin

Stengs

AMNetherlands · Pisa Sporting Club

№ 409344Established €1.7M +0.99

Player dossierSerie A

CalvinStengs

AMAttacking MidfieldMidfield

Club
Pisa Sporting Club
League
Serie A
Nationality
Netherlands
Age
27
Height
187 cm
Foot
Left
Valued
29 May 2026

Reading the valuation

The market values Stengs at €4.5M. Model A, which never saw Stengs during training, estimates €1.7M: the market value is 168% above that estimate.

That is a factor of ×2.68. 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 €1.4M, 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.

▲ +0.99A €1.7M▲ +1.18B €1.4M
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
20
Minutes
839
Goals
1
Assists
4
Started
8/20
Min / app
42
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 Stengs…

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 €1.7M

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 1,687 midfielders

Calvin Stengs's percentiles among midfielders: Goals per 90 58th, Assists per 90 99th, Minutes, two years 10th, Starts 12th, Minutes, last 365 days 2nd, European club minutes 71st58thGoals99thAssists10thMinutes12thStarts2ndRecent71stEurope

Dashed ring: the midfielder median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.43 this player0.09 midfielder median99th percentile

0.00peer deciles · median line · this player ●0.74

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
€50k
Dec 2016
Peak
€20M
Dec 2019
Model target
€4.5M
May 2026
Valuations
27
5 club changes
May 2026€4.5MPisa Sporting ClubValuation the model is trained to reproduce

May 2026: €4.5M, Pisa Sporting Club. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-12-14€50kAZ Alkmaar U21
2017-01-18€100kAZ Alkmaar U21
2017-06-07€500kAZ Alkmaar U21
2018-01-17€500kAZ Alkmaar
2018-06-12€500kAZ Alkmaar
2018-12-28€1MAZ Alkmaar
2019-03-13€5.5MAZ Alkmaar
2019-06-12€7MAZ Alkmaar
2019-09-19€12MAZ Alkmaar
2019-12-18€20MAZ Alkmaar
2020-04-08€18MAZ Alkmaar
2020-10-14€18MAZ Alkmaar
2021-01-06€16MAZ Alkmaar
2021-03-06€15MAZ Alkmaar
2021-05-19€14MAZ Alkmaar
2021-10-08€15MOGC Nice
2021-12-16€15MOGC Nice
2022-05-30€13MOGC Nice
2022-11-04€11MRoyal Antwerp FC
2023-06-09€10MRoyal Antwerp FC
2023-12-15€15MFeyenoord Rotterdam
2024-05-31€15MFeyenoord Rotterdam
2024-12-17€12MFeyenoord Rotterdam
2025-03-28€8MFeyenoord Rotterdam
2025-05-28€7MFeyenoord Rotterdam
2025-12-23€6MPisa Sporting Club
2026-05-29€4.5MPisa Sporting Club

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
+0.986

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 →

Midfielders, all leagues1,687 players · median €2M

Valued above 64% of the 1,687 midfielders.

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

Where Stengs 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).