FairValue

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Alistair

Johnston

RBCanada · Celtic FC

№ 637446Established €4.5M +0.58

Player dossierPremiership

AlistairJohnston

RBRight-BackDefender

Club
Celtic FC
League
Premiership
Nationality
Canada
Age
27
Height
180 cm
Foot
Right
Valued
20 May 2026

Reading the valuation

The market values Johnston at €8M. Model A, which never saw Johnston during training, estimates €4.5M: the market value is 79% above that estimate.

That is a factor of ×1.79. 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 €6.3M, 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.

▲ +0.58A €4.5M▲ +0.25B €6.3M
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
48
Minutes
3,965
Goals
4
Assists
10
Started
47/48
Min / app
83
Cards
5Y 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 Johnston…

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 €8M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €8MModel A €4.5M

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

Alistair Johnston's percentiles among defenders: Goals per 90 84th, Assists per 90 97th, Minutes, two years 68th, Starts 92nd, Minutes, last 365 days 8th, European club minutes 88th84thGoals97thAssists68thMinutes92ndStarts8thRecent88thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.23 this player0.04 defender median97th percentile

0.00peer deciles · median line · this player ●0.58

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
Feb 2020
Peak
€10M
Mar 2025
Model target
€8M
May 2026
Valuations
19
2 club changes
May 2026€8MCeltic FCValuation the model is trained to reproduce

May 2026: €8M, Celtic FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2020-02-28€50kNashville SC
2020-08-26€50kNashville SC
2020-11-13€500kNashville SC
2020-12-18€2MNashville SC
2021-07-09€2.5MNashville SC
2021-11-09€2.5MNashville SC
2022-03-27€3MCF Montréal
2022-08-18€4MCF Montréal
2022-11-08€6MCF Montréal
2023-06-26€7MCeltic FC
2023-12-05€7.5MCeltic FC
2024-03-20€8MCeltic FC
2024-05-30€8.5MCeltic FC
2024-12-03€9MCeltic FC
2025-03-12€10MCeltic FC
2025-06-17€10MCeltic FC
2025-10-08€9MCeltic FC
2025-12-10€8MCeltic FC
2026-05-20€8MCeltic FC

Audit context group-level, not about this player

Audit group
non-UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
+0.582

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 →

Premiership311 players · median €400k

Joint 10th highest observed value among 311 Premiership players.

€20k€150k€1M€7.5M€8MSee them in the Explorer →

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

Valued above 78% of the 2,065 defenders.

€20k€200k€2M€20M€8MSee them in the Explorer →

Where Johnston 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).