Interislander Ferry

Ranking Score Explained

G'day, thanks for your interest in how we calculate an experience's ranking score. It's at the core of Rankers so I'm pleased you're curious.

The ranking score percentage is used to compare and sort experiences in ranking tables. It is not necessarily a direct measurement of the quality of a particular experience as rated by its customers. I've found it a useful tool to allow me to find the best experiences with confidence. But I've also found it important to read the customer reviews before making any final judgements!

We calculate an experience's ranking score using a multi-factor data model instead of a raw data average (mean). This model takes into account several important questions. For instance - is there a trusted body of reviews? What is the age of a review and is the review from a credible source?

Below you'll find details around some of the important factors that went into calculating the ranking score for Interislander Ferry.

If you have any questions or comments about our ranking score calculation please get in touch at info@rankers.co.nz. We don't believe this is perfect or complete so we're always interested in ways we might make improvements.

Cymen Crick

Rankers Owner

Valid Reviews

353 Valid Reviews

The Interislander Ferry experience has a total of 364 reviews. There are 353 valid reviews that are included when calculating the ranking score and 11 invalid reviews that are excluded from the calculation. Reviews can be excluded only when a reviewer is not verified or after an investigation by our team determines the reviewer is not genuine.

Below is the distribution of ratings for the 353 valid reviews:

Rating	Count
10/10	41	12%
9/10	81	23%
8/10	103	29%
7/10	62	18%
6/10	29	8%
5/10	16	5%
4/10	7	2%
3/10	5	1%
2/10	3	1%
1/10	6	2%

76.66% Average

The raw data average (mean) for all the Interislander Ferry valid reviews is 76.66% and is based on 353 valid reviews. This value is not used to calculate the ranking score and it only provided here as a comparison to the weighted average.

Face-to-Face Reviews

309 Face-to-Face Reviews

The Rankers team meets with travellers while they’re in New Zealand and conducts face-to-face surveys. These reviews, in our opinion, are the most trusted in the industry and represent a critical control sample. To our knowledge, we are the only travel review website in the world that has gone to this extent.

More about face-to-face reviews

Within the 353 valid reviews, the experience has 309 face-to-face reviews collected during interviews by our team.

Below is the distribution of ratings for the 309 face-to-face reviews:

Rating	Count
10/10	30	10%
9/10	70	23%
8/10	98	32%
7/10	58	19%
6/10	25	8%
5/10	15	5%
4/10	6	2%
3/10	4	1%
2/10	2	1%
1/10	1	0%

77.22% Average

The raw data average (mean) for all the Interislander Ferry face-to-face reviews is 77.22% and is based on 309 face-to-face reviews. This value is not used to calculate the ranking score and it only provided here for comparison purposes.

Weighted Average

69.04%

Rankers calculates a weighted mean as a base average on which we can improve. Individual review's ratings are given a weight based on several factors. The weight of a review determines the overall impact it'll have on the final weighted average.

Recent reviews have more weight as they are more relevant and reflect the experience as it currently operates. Over time reviews become less relevant and loose their impact on the ranking score.

Low rating reviews carry slightly less weight. This dampens the effect of very low ratings for every experience across the board. This is especially important when the experience has few reviews overall and a single negative rating can grossly mischaracterise an experience. Consistent poor reviews will still result in the experience receiving a comparitively low ranking score.

Credible sources provide reviews that can be trusted. If we have verified a reviewer is genuine via a face-to-face meeting then the review carries additional weight.

Reviewer	Rating	Age	Relative Weight
Herb Klein	2/10	232 days	46%
Nico	1/10	232 days	41%
Ruban K	1/10	260 days	41%
Maria Longstaff	10/10	291 days	100%
Rina	9/10	413 days	94%
edm	1/10	687 days	31%
Colin Barrow	9/10	748 days	71%
Pauline	6/10	901 days	48%
Megan	5/10	1053 days	31%
Marjolaine Loitz	4/10	1083 days	25%
Keli Knox	10/10	1418 days	15%
Yar	1/10	1632 days	3%
Pinocity	6/10	1997 days	4%
Helen Russell	10/10	2178 days	4%
NewZealander	10/10	2452 days	4%
Tommy Pickett	9/10	3275 days	2%
Tom Bennett	8/10	3279 days	2%
Jeny Smolders	9/10	3281 days	2%
Gregg Wagstaff	7/10	3506 days	1%
Lianne Ijlst	8/10	3534 days	1%
Samantha and Neis	8/10	3535 days	1%
Brandon Cassidy	7/10	3551 days	1%
Vic Baughen	9/10	3553 days	1%
Anders Frank	7/10	3557 days	1%
Dina Schurer	8/10	3558 days	1%
Kim Youngsub	9/10	3559 days	1%
DEBBIE LAMBERT	10/10	3563 days	1%
Gary Williams	8/10	3563 days	1%
Kimberley Gardien	8/10	3570 days	1%
Antoine	9/10	3591 days	1%
Judit Van lanen	9/10	3596 days	1%
Bjorn Nielsen	8/10	3598 days	1%
Joel Virtanen	9/10	3600 days	1%
Corbin Hure	7/10	3600 days	1%
Ron	6/10	3603 days	1%
Thomas Simeon	8/10	3603 days	1%
Suzannah Hill	8/10	3604 days	1%
Kallan Mrozek	9/10	3605 days	1%
Kees Mol	9/10	3609 days	1%
Kristal Lavender	10/10	3609 days	1%
Bastian Bley	9/10	3610 days	1%
Jasmine Rogers	3/10	3611 days	1%
Louis Nilsson	8/10	3615 days	1%
Tim	7/10	3615 days	1%
Jendrik	6/10	3615 days	1%
Katharina	7/10	3616 days	1%
Chris Valchero	9/10	3619 days	1%
Rulp Niet	8/10	3621 days	1%
Soeren Buchheister	9/10	3622 days	1%
Chas Bronson	8/10	3622 days	1%
Jakob Lovdahl	9/10	3624 days	1%
Alexandra Schmidt	10/10	3634 days	1%
Jade Williams	10/10	3635 days	1%
Sam Staines	10/10	3636 days	1%
Nickolas Jonkergouw	7/10	3640 days	1%
Kirsty Smith	10/10	3640 days	1%
Eva Hesse	10/10	3655 days	1%
celine gries	8/10	3655 days	1%
tinagermany111	8/10	3669 days	1%
Cassandra Geyer	8/10	3854 days	1%
Olivier Reculeau	8/10	3855 days	1%
Thomas Michel	5/10	3856 days	1%
Lisa Haedrich	5/10	3860 days	1%
Nadja Guiliani	8/10	3864 days	1%
Elbrich	8/10	3864 days	1%
Jamie Serieux	7/10	3867 days	1%
Adele Jacques	9/10	3868 days	1%
Daniel Weber	6/10	3870 days	1%
Emily Noyd	8/10	3872 days	1%
Aparna Gula	10/10	3873 days	1%
Sebastiaan	7/10	3875 days	1%
Andre	9/10	3876 days	1%
Benedikt Hang	7/10	3877 days	1%
Yannick	8/10	3877 days	1%
S Black	9/10	3878 days	1%
Paul Larauze	6/10	3881 days	1%
Florence	6/10	3882 days	1%
Sarah Kovacs	8/10	3883 days	1%
Frenziska Schmid	7/10	3885 days	1%
Maud Livolsi	7/10	3892 days	1%
Lewis Whittle	6/10	3894 days	1%
Lukas Seager	6/10	3894 days	1%
Andrea Tabaka	8/10	3901 days	1%
Tina Rust	8/10	3903 days	1%
Joel Papak	8/10	3905 days	1%
Clemence and Pedro	9/10	3906 days	1%
Doms Wahlelr	9/10	3908 days	1%
Josef Biller	8/10	3908 days	1%
Justine Hoffmann	8/10	3909 days	1%
Friederike East	7/10	3909 days	1%
Mark White	10/10	3910 days	1%
Briony	8/10	3913 days	1%
Gabriel Siibers	8/10	3913 days	1%
Henry Wichler	8/10	3914 days	1%
Kyle Johnson	9/10	3916 days	1%
Niels Wezenberg	7/10	3917 days	1%
John Hamilton	9/10	3917 days	1%
Brianna Burd	9/10	3917 days	1%
Jessica Ruhland	8/10	3918 days	1%
Stula Vladimir	10/10	3919 days	1%
Cosmo Hartuna	7/10	3921 days	1%
Roland Fischer	6/10	3921 days	1%
Ross Holmes	9/10	3922 days	1%
Tilman	9/10	3924 days	1%
Petru	7/10	3925 days	1%
Fero Saarinen	6/10	3926 days	1%
Lauren Thompson	8/10	3928 days	1%
Meilin	8/10	3931 days	1%
Jonas Hoerning	10/10	3935 days	1%
Vanesha Patel	6/10	3936 days	1%
Mauricio Daniele	9/10	3936 days	1%
Sara and Antoine	8/10	3938 days	1%
Clare Pickford	6/10	3938 days	1%
Daniel Hill	10/10	3939 days	1%
Moritz Braun	7/10	3955 days	1%
Grischa Rodust	8/10	3962 days	1%
Chalie Dotesek	9/10	3963 days	1%
Julien Lafeville	7/10	3967 days	1%
Julia Huesam	8/10	3967 days	1%
Alexandre	9/10	3971 days	1%
Kev Zarka	6/10	3972 days	0%
Markus Wabing	8/10	3975 days	1%
Gessica	6/10	4008 days	0%
Simon Quass	9/10	4012 days	0%
Barthelemy	7/10	4241 days	0%
Brita Topp	10/10	4584 days	1%
Laim Thompson	8/10	4584 days	1%
Adriana	10/10	4592 days	1%
Pavel Jarolimek	5/10	4592 days	1%
Leonie Moeller	6/10	4593 days	1%
Doreen Gendel	8/10	4594 days	1%
Carla Oyarzun	3/10	4597 days	0%
Paolo Cases	3/10	4597 days	0%
Wolfgang and Christine	8/10	4602 days	1%
Helen	8/10	4615 days	1%
Olivier Carval	9/10	4617 days	1%
Hirsch Svenja	9/10	4618 days	1%
Mahr Svenja	8/10	4618 days	1%
Anna Guzewiez	9/10	4634 days	1%
Pier Durand	8/10	4638 days	1%
Serena Poggioli	9/10	4638 days	1%
Wayne Schist	7/10	4638 days	1%
Margreth Lydie	5/10	4646 days	1%
Laura Pleumeekers	7/10	4660 days	1%
David Brooks	10/10	4663 days	1%
Adrien Godeloup	9/10	4672 days	1%
Bet Dreno	8/10	4673 days	1%
Joachim	1/10	4674 days	0%
Pioter Jurkowski	7/10	4674 days	1%
Thomas Roche	9/10	4676 days	1%
Brian	9/10	4735 days	1%
hendrik king	9/10	4858 days	1%
Kiki Wykstra	5/10	4968 days	1%
Galen Licht	4/10	4968 days	0%
Yu-Ti Chu	7/10	4971 days	1%
Ton Martens	7/10	4971 days	1%
Joshua Perry	8/10	4976 days	1%
Molly Ladd	8/10	4976 days	1%
Michael Nolan	9/10	4980 days	1%
Julian Roots	9/10	4980 days	1%
Florent Corino	9/10	4984 days	1%
Amiot Cyriane	7/10	4984 days	1%
Annika	7/10	4984 days	1%
Jonas Herrmann	7/10	4984 days	1%
Matthieu Daveou	8/10	4984 days	1%
Julien Panossian	6/10	4984 days	1%
Raoul Montestruer	5/10	4984 days	1%
Alessa Ndra	8/10	4990 days	1%
Bjorn Hedmark	5/10	4991 days	1%
Evyatar Tulipman	7/10	4993 days	1%
S Curry	10/10	5008 days	1%
Ingrid	9/10	5052 days	1%
Reinier Timmer	7/10	5052 days	1%
Moorman	8/10	5061 days	1%
Stefan Roth	9/10	5086 days	1%
David	9/10	5100 days	1%
kevindang	10/10	5253 days	1%
Ruben Kunze	4/10	5335 days	0%
Sebastian Hol	9/10	5341 days	1%
Dick Stewart	8/10	5350 days	1%
David Beaumont	9/10	5357 days	1%
Beyeler	10/10	5362 days	1%
Nikita Sue	9/10	5367 days	1%
Schweiger	10/10	5369 days	1%
Jan & Marian	10/10	5448 days	1%
Konny	9/10	5452 days	1%
Waldemar Schuler	8/10	5452 days	1%
jule	3/10	5466 days	0%
Jack Potman	8/10	5668 days	1%
Jon_and_Family	9/10	5680 days	1%
Walker	9/10	5683 days	1%
Andreas Blessing	10/10	5691 days	1%
Gema	7/10	5694 days	1%
Avry Fabrice	6/10	5699 days	1%
Diane Johnston	9/10	5704 days	1%
Javier Munoz	8/10	5704 days	1%
Ben Akin-Smith	8/10	5705 days	1%
K Wallis	9/10	5710 days	1%
khs	9/10	5711 days	1%
Emma Ducat	9/10	5711 days	1%
Mr and Mrs Lambert	8/10	5718 days	1%
Andrew Koster	7/10	5724 days	1%
Bakker	8/10	5724 days	1%
Kimberly St Louis	8/10	5725 days	1%
Roel Wesstra	8/10	5731 days	1%
Seifert	10/10	5731 days	1%
Derek Woodward	9/10	5733 days	1%
Fabi & Sabi	8/10	5734 days	1%
Rosey834	8/10	5801 days	1%
Pete & Chris	10/10	6001 days	1%
Tony Masters	9/10	6064 days	1%
Hershell	8/10	6068 days	1%
Mike Robinson	9/10	6069 days	1%
Brent S	2/10	6070 days	0%
Zara Leyden	9/10	6078 days	1%
Judith	7/10	6082 days	1%
anon	8/10	6083 days	1%
Pierre Pilon	8/10	6084 days	1%
Jenny Omb	1/10	6089 days	0%
Frei Urs	6/10	6090 days	1%
Bryan Keddie	9/10	6100 days	1%
Leanne Rogan	5/10	6100 days	1%
Joanne Clarke	8/10	6104 days	1%
Wolfgang G	9/10	6110 days	1%
Thomas Signes	7/10	6131 days	1%
menzel	10/10	6149 days	1%
graemeh1	9/10	6150 days	1%
klinger	10/10	6150 days	1%
gereldineb	8/10	6160 days	1%
jennyb	9/10	6164 days	1%
Frank de Voogd	8/10	6170 days	1%
Jean Paul Mesnage	9/10	6176 days	1%
Hansjoerg Ehrmann	5/10	6177 days	1%
Daniel Alonso	9/10	6178 days	1%
Nigel Petrie	9/10	6189 days	1%
Tracy & Peter Cassidy	8/10	6205 days	1%
miniappleses	8/10	6227 days	1%
Josie Boyle	7/10	6338 days	1%
JanneP	9/10	6408 days	1%
Mikey	9/10	6415 days	1%
SablotniD	7/10	6419 days	1%
WiebkeS	9/10	6426 days	1%
Tanya	5/10	6427 days	1%
Jan	6/10	6427 days	1%
Viola	8/10	6429 days	1%
RowanL	7/10	6430 days	1%
VickiEngland	8/10	6438 days	1%
TomC1	8/10	6443 days	1%
AndyK	9/10	6443 days	1%
TatiamT	9/10	6443 days	1%
GillianK	8/10	6445 days	1%
EelcoK	9/10	6445 days	1%
Michael	9/10	6449 days	1%
soccaplaya14	10/10	6450 days	1%
Eugene	7/10	6451 days	1%
John	6/10	6453 days	1%
Tony	8/10	6458 days	1%
Middleton	4/10	6459 days	0%
Elise	8/10	6460 days	1%
Marie	8/10	6460 days	1%
ThomasS1	10/10	6465 days	1%
RasmusB	4/10	6467 days	0%
Simon	8/10	6472 days	1%
Phil&Joe	10/10	6474 days	1%
Marcus	7/10	6474 days	1%
Andre	7/10	6476 days	1%
Iris	9/10	6478 days	1%
Carla	7/10	6478 days	1%
Sandra	8/10	6482 days	1%
Schaffluber	10/10	6483 days	1%
Hayley	5/10	6484 days	1%
Con	2/10	6528 days	0%
felix	7/10	6529 days	1%
melissa	10/10	6536 days	1%
John B	5/10	6538 days	1%
Gemma	7/10	6577 days	1%
Henry	7/10	6577 days	1%
Antonella	10/10	6584 days	1%
Michelle	8/10	6584 days	1%
Laura	7/10	6593 days	1%
Sarah	8/10	6608 days	1%
Katerina	7/10	6628 days	1%
Erin	3/10	6628 days	0%
Mike Knight	9/10	6649 days	1%
Bronagh Mcartan	8/10	6658 days	1%
Dave	8/10	6669 days	1%
fgregory	10/10	6672 days	1%
Rhea	6/10	6718 days	1%
Georgina Mulligan	8/10	6730 days	1%
Karen C	7/10	6742 days	1%
Edmund Hillstone	10/10	6759 days	1%
Toby	6/10	6782 days	1%
Jennifer Baulch	9/10	6786 days	1%
Susan	8/10	6790 days	1%
Hoetnagels	7/10	6793 days	1%
Alan Bellerby	8/10	6796 days	1%
Sanne Jonker	7/10	6797 days	1%
Renske Tehurne	8/10	6801 days	1%
Benjamin Krein	7/10	6801 days	1%
Anne and Derek	8/10	6802 days	1%
James Davies	7/10	6802 days	1%
Naomi Horton	8/10	6803 days	1%
Roger Repolusk	8/10	6807 days	1%
Tony Wicks	6/10	6807 days	1%
Nancy Dol	8/10	6807 days	1%
Kristine	10/10	6807 days	1%
Kathy Hawey	9/10	6809 days	1%
David Buckley	8/10	6810 days	1%
Lena1	6/10	6810 days	1%
John Woodrow	8/10	6811 days	1%
Carmen Dolny	10/10	6811 days	1%
Haemnerli	8/10	6815 days	1%
Carla	8/10	6822 days	1%
Jim Curley	8/10	6822 days	1%
paulonline	7/10	6828 days	1%
Bex	6/10	6837 days	1%
Jenny Hulsebosch	8/10	6838 days	1%
Melissa Steedman	8/10	6849 days	1%
Tim	7/10	6850 days	1%
Falk Seidel	7/10	6853 days	1%
Hans Olthof	8/10	6853 days	1%
Anu	9/10	6856 days	1%
Anneli	6/10	6858 days	1%
purplekat99	10/10	6866 days	1%
Connor	10/10	6879 days	1%
Ad	7/10	6879 days	1%
Ann Westmacott	5/10	6884 days	1%
Paul Cowie	8/10	6885 days	1%
Ewen Maclean	8/10	6885 days	1%
Sarah Wilton	5/10	6885 days	1%
Arend v Dyn	7/10	6887 days	1%
Linda	8/10	6891 days	1%
Fiona	7/10	6891 days	1%
Ann	7/10	6892 days	1%
ranker_584	9/10	6895 days	1%
Christine	7/10	6895 days	1%
Nina	9/10	6895 days	1%
Anthony	7/10	6900 days	1%
Tom Clements	7/10	6900 days	1%
ranker_46	8/10	7012 days	1%
Pat Brewster	8/10	7012 days	1%
FrankOosterwijk	6/10	7097 days	1%
Kim	8/10	7097 days	1%
Helen	7/10	7128 days	1%
Heather	9/10	7128 days	1%
Helene	9/10	7140 days	1%
John	7/10	7140 days	1%
Giancarlo	6/10	7140 days	1%
Annette	4/10	7164 days	0%
John	5/10	7164 days	1%
Duncan	9/10	7169 days	1%
Jen	4/10	7180 days	0%
Rolf	8/10	7188 days	1%

Adjustments

Several adjustments to the weighted average are added to improve relevancy and credibility. These adjustments apply equally to all experiences that meet the criteria.

Sample Size Adjustment

No Adjustment

A reasonable number of reviews are necessary in order for the average to be credible and for an experience to take a prime position within the ranking tables. As such, experiences with only a few reviews have a moderated score. This does not mean that the experience or the reviews can't be trusted. The Interislander Ferry experience has plenty of reviews and does not meet the criteria for any adjustment.

Recent Reviews Adjustment

-3.64% Adjustment

There may be an adjustment if this experience hasn't received any reviews within the last 57 days. However the Interislander Ferry experience does not meet the criteria for any adjustment.

In addition, an experience's ranking score may be adjusted for each day there is no new ranking. After 1 day the adjustment comes into effect. The maximum number of days that can be adjusted for is 200 days. Due to the seasonal nature of many businesses, this adjustment is applied dynamically throughout the year.

The Interislander Ferry experience has been adjusted for 200 days. Adjustments are according to the following table.

Days	Adjustment
…	…
197	-3.59%
198	-3.60%
199	-3.62%
200	-3.64%
201	-3.66%
202	-3.68%
203	-3.70%
…	…

Balancing Adjustment

9.93% Adjustment

Every experience's review score is adjusted to balance out the disproportional number of negative reviews that are contributed.

You won't be surprised to learn that disgruntled customers are more likely to leave a review than happy ones. They are motivated to share their experience and warn others. We consider this a good thing and it's why reading the reviews is important. However we've learned it can misrepresent the experience in a more overall sense.

We apply a balancing adjustment to counteract this effect and ensure the ranking score is a more fair representation of the experience. This adjustment is applied equally to all experiences.

Final Ranking Score

75%

The final ranking score once any adjustments, ratings, and rounding has been applied. This value is recalculated each day and a short rolling average is applied. Therefore it may not be precisely accurate based on the other values presented.