FairValue

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Jens Martin

Gammelby

RBDenmark · Silkeborg IF

№ 265040Emerging €564k −0.48

Player dossierSuperliga

Jens MartinGammelby

RBRight-BackDefender

Club
Silkeborg IF
League
Superliga
Nationality
Denmark
Age
31
Height
192 cm
Foot
Both
Valued
25 May 2026

Reading the valuation

The market values Gammelby at €350k. Model A, which never saw Gammelby during training, estimates €564k: the market value is 38% below that estimate.

That is a factor of ×1.61. 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 €733k, 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.

▼ −0.48A €564k▼ −0.74B €733k
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
46
Minutes
3,458
Goals
8
Assists
3
Started
37/46
Min / app
75
Cards
3Y 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 Gammelby…

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 €564k

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

Jens Martin Gammelby's percentiles among defenders: Goals per 90 99th, Assists per 90 70th, Minutes, two years 61st, Starts 46th, Minutes, last 365 days 80th, European club minutes 73rd99thGoals70thAssists61stMinutes46thStarts80thRecent73rdEurope

Dashed ring: the defender median (50th percentile)

Goals per 90

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

0.21 this player0.03 defender median99th 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
€50k
Apr 2014
Peak
€800k
Jun 2019
Model target
€350k
May 2026
Valuations
28
8 club changes
May 2026€350kSilkeborg IFValuation the model is trained to reproduce

May 2026: €350k, Silkeborg IF. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2014-04-17€50kSilkeborg IF U19
2014-06-26€200kSilkeborg IF U19
2015-02-06€350kSilkeborg IF U19
2015-09-02€250kSilkeborg IF
2016-01-25€200kSilkeborg IF
2016-08-12€300kSilkeborg IF
2016-12-12€350kSilkeborg IF
2017-06-21€400kSilkeborg IF
2017-12-18€500kSilkeborg IF
2018-06-02€700kSilkeborg IF
2018-12-21€600kBröndby IF
2019-06-08€800kBröndby IF
2019-09-09€600kBröndby IF
2019-12-22€400kBröndby IF
2020-04-08€325kBröndby IF
2020-07-31€600kBröndby IF
2020-12-23€500kLyngby Boldklub
2021-06-04€500kLyngby Boldklub
2021-12-28€500kBröndby IF
2022-06-24€500kMiedz Legnica
2022-12-22€500kBröndby IF
2023-06-29€400kHamarkameratene
2023-12-15€400kHamarkameratene
2024-06-10€450kSilkeborg IF
2024-12-09€350kSilkeborg IF
2025-06-16€350kSilkeborg IF
2025-12-15€350kSilkeborg IF
2026-05-25€350kSilkeborg IF

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
−0.477

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 →

Superliga256 players · median €800k

Valued above 14% of the 256 Superliga players.

€20k€150k€1M€7.5M€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 Gammelby 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).