FairValue

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Joey

Jacobs

CBNetherlands · Almere City FC

№ 361124Emerging €432k −0.21

Player dossierEredivisie

JoeyJacobs

CBCentre-BackDefender

Club
Almere City FC
League
Eredivisie
Nationality
Netherlands
Age
25
Height
187 cm
Foot
Right
Valued
16 Dec 2025

Reading the valuation

The market values Jacobs at €350k. Model A, which never saw Jacobs during training, estimates €432k: the market value is 19% below that estimate.

That is a factor of ×1.23. 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 €1.3M, 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.

▼ −0.21A €432k▼ −1.33B €1.3M
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
39
Minutes
2,593
Goals
1
Assists
0
Started
31/39
Min / app
66
Cards
5Y 2R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Jacobs…

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 €350k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €350kModel A €432k

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

Joey Jacobs's percentiles among defenders: Goals per 90 53rd, Assists per 90 17th, Minutes, two years 45th, Starts 43rd, Minutes, last 365 days 8th, European club minutes 30th53rdGoals17thAssists45thMinutes43rdStarts8thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Goals per 90

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

0.03 this player0.03 defender median53rd 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
€25k
Jul 2019
Peak
€650k
Mar 2024
Model target
€350k
Dec 2025
Valuations
17
1 club change
Dec 2025€350kAlmere City FCValuation the model is trained to reproduce

Dec 2025: €350k, Almere City FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2019-07-03€25kAZ Alkmaar U21
2020-06-29€125kAZ Alkmaar U21
2020-10-24€200kAZ Alkmaar U21
2020-12-31€350kAZ Alkmaar U21
2021-10-12€350kAZ Alkmaar U21
2022-01-12€450kAlmere City FC
2022-06-23€450kAlmere City FC
2023-04-03€300kAlmere City FC
2023-07-04€350kAlmere City FC
2023-12-15€450kAlmere City FC
2024-03-18€650kAlmere City FC
2024-05-31€650kAlmere City FC
2024-10-14€500kAlmere City FC
2024-12-17€500kAlmere City FC
2025-03-28€400kAlmere City FC
2025-05-28€350kAlmere City FC
2025-12-16€350kAlmere City FC

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
−0.210

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 14% of the 425 Eredivisie players.

€75k€500k€3M€20M€350kSee them in the Explorer →

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

Valued above 12% of the 2,065 defenders.

€20k€200k€2M€20M€350kSee them in the Explorer →

Where Jacobs 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).