FairValue

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Devon

Koswal

CBNetherlands · SC Telstar

№ 748604Emerging €680k −0.41

Player dossierEredivisie

DevonKoswal

CBCentre-BackDefender

Club
SC Telstar
League
Eredivisie
Nationality
Netherlands
Age
22
Height
192 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Koswal at €450k. Model A, which never saw Koswal during training, estimates €680k: the market value is 34% below that estimate.

That is a factor of ×1.51. 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 €1.5M, 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.

▼ −0.41A €680k▼ −1.23B €1.5M
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
27
Minutes
1,818
Goals
0
Assists
0
Started
20/27
Min / app
67
Cards
4Y 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 Koswal…

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 €450k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €450kModel A €680k

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

Devon Koswal's percentiles among defenders: Goals per 90 18th, Assists per 90 17th, Minutes, two years 30th, Starts 33rd, Minutes, last 365 days 55th, European club minutes 30th18thGoals17thAssists30thMinutes33rdStarts55thRecent30thEurope

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.

1,818 this player1,687 defender median55th 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
Mar 2021
Peak
€500k
Dec 2025
Model target
€450k
May 2026
Valuations
13
1 club change
May 2026€450kSC TelstarValuation the model is trained to reproduce

May 2026: €450k, SC Telstar. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2021-03-16€200kFC Dordrecht
2021-10-12€175kFC Dordrecht
2022-01-12€100kFC Dordrecht
2022-06-23€100kFC Dordrecht
2023-07-04€75kFC Dordrecht
2024-01-08€150kSC Telstar
2024-06-10€200kSC Telstar
2024-10-14€250kSC Telstar
2024-12-10€250kSC Telstar
2025-03-14€300kSC Telstar
2025-06-09€350kSC Telstar
2025-12-02€500kSC Telstar
2026-05-28€450kSC Telstar

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
−0.413

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 →

Eredivisie425 players · median €1M

Valued above 22% of the 425 Eredivisie players.

€75k€500k€3M€20M€450kSee them in the Explorer →

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

Valued above 17% of the 2,065 defenders.

€20k€200k€2M€20M€450kSee them in the Explorer →

Where Koswal 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).