Methodology
Luxury Ship Index helps readers understand luxury cruise ships through technical specifications, independently calculated metrics and plain-English interpretation. The methodology answers one question: what do a ship's numbers and design choices imply for the traveller?
Short answer
Every analytical page on Luxury Ship Index separates three categories: verified specifications (sourced from official cruise lines, shipyards and classification societies), calculated metrics (deterministic formulas applied to those specifications) and editorial interpretation (plain-English commentary, never blurred with the first two).
Key claims
- Ratios are calculated deterministically from the canonical ship database, not estimated by writers.
- GT per guest, crew per 100 guests and suites per 100 guests are the primary density indicators.
- Each ship profile carries a high / medium / low data-confidence rating tied to source quality.
- Ships are scored against peer groups, not across them — a yacht-style vessel is not benchmarked against a resort ship.
- In-service ship profiles are reviewed every six months; newbuilds every one to three months.
Data categories
Each article separates three categories. They are never blurred:
- Verified specifications — sourced from cruise lines, shipyards, classification societies, official deck plans, regulatory data or reputable industry sources.
- Calculated metrics — derived from verified facts using fixed formulas, generated
by
@seokone/enginerather than typed by an editor. - Editorial interpretation — what the facts and metrics may mean for the reader. Always labelled as interpretation, never presented as a measurement.
Unit convention
Locale is en-GB. Metric primary, imperial in parentheses where space allows: 230 m (755 ft). Gross tonnage is shown as
GT; speed is shown in knots. Currency, when it appears, uses pounds sterling.
Calculated ratios
- GT per guest
-
gross_tonnage / guest_capacity. Ship volume relative to guest capacity. A density indicator, not a usable-floor-area measurement. - Guests per crew member
-
guest_capacity / crew_count. Lower numbers suggest stronger potential service density. Does not prove service quality. - Crew per 100 guests
-
crew_count / guest_capacity * 100. Easier to read than a raw ratio. - Suites per 100 guests
-
suite_count / guest_capacity * 100. Identifies how suite-focused a ship is. Note: an all-suite vessel under double occupancy sits near 50, not 100. - GT per suite
-
gross_tonnage / suite_count. Rough measure of ship volume relative to accommodation inventory.
Data confidence
Each ship profile carries one of three confidence ratings. The rating is the worst component confidence inside the score model:
- High — official cruise line, shipyard or classification source available; key fields consistent across sources; launch / refit status current.
- Medium — some data from reputable industry sources; minor source conflicts; one or two secondary fields missing.
- Low — official data unavailable; multiple source conflicts; pre-launch ship with incomplete public data; important technical fields missing.
Peer groups
Ships are scored and compared inside relevant peer groups. We do not rank a 95-suite yacht-style ship directly against a large resort ship.
- Ultra-luxury ocean
- Yacht luxury
- Expedition luxury
- Classic luxury
- Premium-luxury-adjacent
Refresh cadence
| Content type | Review cadence |
|---|---|
| In-service ship profiles | 6 months |
| Newbuild ship profiles | 1–3 months |
| Comparison pages | 12 months or when data changes |
| Rankings | 3 months |
| Technical guides | 12 months |
| Newbuild tracker | 1 month |
| Methodology pages | 12 months |
Luxury Ship Index Score
The Luxury Ship Index Score is an editorial 0–100 metric built from seven weighted components: space per guest (25), crew-to-guest service density (20), suite exclusivity (15), ship age and refit status (10), public-space design (10), dining and amenity density (10) and technical sophistication (10). The full scoring policy and component formulas live on a dedicated page: how the score is calculated.
Methodology
Luxury Ship Index uses publicly available ship specifications, cruise line documentation, shipyard data, reputable industry sources and independently calculated ratios. Scores are editorial tools, not absolute measures of quality. They are intended to help readers understand how a ship's design and operating profile may affect the onboard experience.
Limitations
Calculated ratios are based on double-occupancy capacity unless the profile states otherwise; full-occupancy ratios may differ. Score components fall back to "low confidence" when their inputs are unknown, and the article-level confidence reflects the worst component confidence. Where a specification is not publicly available at the time of the last review, the field is left blank rather than estimated.
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