Interislander Ferry

Ranking Score Explained

Hi, 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

69.01%

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	171 days	46%
Nico	1/10	171 days	41%
Ruban K	1/10	199 days	41%
Maria Longstaff	10/10	230 days	100%
Rina	9/10	352 days	95%
edm	1/10	626 days	32%
Colin Barrow	9/10	687 days	75%
Pauline	6/10	840 days	53%
Megan	5/10	992 days	35%
Marjolaine Loitz	4/10	1022 days	28%
Keli Knox	10/10	1357 days	18%
Yar	1/10	1571 days	3%
Pinocity	6/10	1936 days	4%
Helen Russell	10/10	2117 days	4%
NewZealander	10/10	2391 days	4%
Tommy Pickett	9/10	3214 days	2%
Tom Bennett	8/10	3218 days	2%
Jeny Smolders	9/10	3220 days	2%
Gregg Wagstaff	7/10	3445 days	1%
Lianne Ijlst	8/10	3473 days	1%
Samantha and Neis	8/10	3474 days	1%
Brandon Cassidy	7/10	3490 days	1%
Vic Baughen	9/10	3492 days	1%
Anders Frank	7/10	3496 days	1%
Dina Schurer	8/10	3497 days	1%
Kim Youngsub	9/10	3498 days	1%
DEBBIE LAMBERT	10/10	3502 days	1%
Gary Williams	8/10	3502 days	1%
Kimberley Gardien	8/10	3509 days	1%
Antoine	9/10	3530 days	1%
Judit Van lanen	9/10	3535 days	1%
Bjorn Nielsen	8/10	3537 days	1%
Joel Virtanen	9/10	3539 days	1%
Corbin Hure	7/10	3539 days	1%
Ron	6/10	3542 days	1%
Thomas Simeon	8/10	3542 days	1%
Suzannah Hill	8/10	3543 days	1%
Kallan Mrozek	9/10	3544 days	1%
Kees Mol	9/10	3548 days	1%
Kristal Lavender	10/10	3548 days	1%
Bastian Bley	9/10	3549 days	1%
Jasmine Rogers	3/10	3550 days	1%
Louis Nilsson	8/10	3554 days	1%
Tim	7/10	3554 days	1%
Jendrik	6/10	3554 days	1%
Katharina	7/10	3555 days	1%
Chris Valchero	9/10	3558 days	1%
Rulp Niet	8/10	3560 days	1%
Soeren Buchheister	9/10	3561 days	1%
Chas Bronson	8/10	3561 days	1%
Jakob Lovdahl	9/10	3563 days	1%
Alexandra Schmidt	10/10	3573 days	1%
Jade Williams	10/10	3574 days	1%
Sam Staines	10/10	3575 days	1%
Nickolas Jonkergouw	7/10	3579 days	1%
Kirsty Smith	10/10	3579 days	1%
Eva Hesse	10/10	3594 days	1%
celine gries	8/10	3594 days	1%
tinagermany111	8/10	3609 days	1%
Cassandra Geyer	8/10	3793 days	1%
Olivier Reculeau	8/10	3794 days	1%
Thomas Michel	5/10	3795 days	1%
Lisa Haedrich	5/10	3799 days	1%
Nadja Guiliani	8/10	3803 days	1%
Elbrich	8/10	3803 days	1%
Jamie Serieux	7/10	3806 days	1%
Adele Jacques	9/10	3807 days	1%
Daniel Weber	6/10	3809 days	1%
Emily Noyd	8/10	3811 days	1%
Aparna Gula	10/10	3812 days	1%
Sebastiaan	7/10	3814 days	1%
Andre	9/10	3815 days	1%
Benedikt Hang	7/10	3816 days	1%
Yannick	8/10	3816 days	1%
S Black	9/10	3817 days	1%
Paul Larauze	6/10	3820 days	1%
Florence	6/10	3821 days	1%
Sarah Kovacs	8/10	3822 days	1%
Frenziska Schmid	7/10	3824 days	1%
Maud Livolsi	7/10	3831 days	1%
Lewis Whittle	6/10	3833 days	1%
Lukas Seager	6/10	3833 days	1%
Andrea Tabaka	8/10	3840 days	1%
Tina Rust	8/10	3842 days	1%
Joel Papak	8/10	3844 days	1%
Clemence and Pedro	9/10	3845 days	1%
Doms Wahlelr	9/10	3847 days	1%
Josef Biller	8/10	3847 days	1%
Justine Hoffmann	8/10	3848 days	1%
Friederike East	7/10	3848 days	1%
Mark White	10/10	3849 days	1%
Briony	8/10	3852 days	1%
Gabriel Siibers	8/10	3852 days	1%
Henry Wichler	8/10	3853 days	1%
Kyle Johnson	9/10	3855 days	1%
Niels Wezenberg	7/10	3856 days	1%
John Hamilton	9/10	3856 days	1%
Brianna Burd	9/10	3856 days	1%
Jessica Ruhland	8/10	3857 days	1%
Stula Vladimir	10/10	3858 days	1%
Cosmo Hartuna	7/10	3860 days	1%
Roland Fischer	6/10	3860 days	1%
Ross Holmes	9/10	3861 days	1%
Tilman	9/10	3863 days	1%
Petru	7/10	3864 days	1%
Fero Saarinen	6/10	3865 days	1%
Lauren Thompson	8/10	3867 days	1%
Meilin	8/10	3870 days	1%
Jonas Hoerning	10/10	3874 days	1%
Vanesha Patel	6/10	3875 days	1%
Mauricio Daniele	9/10	3875 days	1%
Sara and Antoine	8/10	3877 days	1%
Clare Pickford	6/10	3877 days	1%
Daniel Hill	10/10	3878 days	1%
Moritz Braun	7/10	3894 days	1%
Grischa Rodust	8/10	3901 days	1%
Chalie Dotesek	9/10	3902 days	1%
Julien Lafeville	7/10	3906 days	1%
Julia Huesam	8/10	3906 days	1%
Alexandre	9/10	3910 days	1%
Kev Zarka	6/10	3911 days	0%
Markus Wabing	8/10	3914 days	1%
Gessica	6/10	3947 days	0%
Simon Quass	9/10	3951 days	0%
Barthelemy	7/10	4180 days	0%
Brita Topp	10/10	4523 days	1%
Laim Thompson	8/10	4523 days	1%
Adriana	10/10	4531 days	1%
Pavel Jarolimek	5/10	4531 days	0%
Leonie Moeller	6/10	4532 days	1%
Doreen Gendel	8/10	4533 days	1%
Carla Oyarzun	3/10	4536 days	0%
Paolo Cases	3/10	4536 days	0%
Wolfgang and Christine	8/10	4541 days	1%
Helen	8/10	4554 days	1%
Olivier Carval	9/10	4556 days	1%
Hirsch Svenja	9/10	4557 days	1%
Mahr Svenja	8/10	4557 days	1%
Anna Guzewiez	9/10	4573 days	1%
Pier Durand	8/10	4577 days	1%
Serena Poggioli	9/10	4577 days	1%
Wayne Schist	7/10	4577 days	1%
Margreth Lydie	5/10	4585 days	0%
Laura Pleumeekers	7/10	4599 days	1%
David Brooks	10/10	4602 days	1%
Adrien Godeloup	9/10	4611 days	1%
Bet Dreno	8/10	4612 days	1%
Joachim	1/10	4613 days	0%
Pioter Jurkowski	7/10	4613 days	1%
Thomas Roche	9/10	4615 days	1%
Brian	9/10	4674 days	1%
hendrik king	9/10	4797 days	1%
Kiki Wykstra	5/10	4907 days	0%
Galen Licht	4/10	4907 days	0%
Yu-Ti Chu	7/10	4910 days	1%
Ton Martens	7/10	4910 days	1%
Joshua Perry	8/10	4915 days	1%
Molly Ladd	8/10	4915 days	1%
Michael Nolan	9/10	4919 days	1%
Julian Roots	9/10	4919 days	1%
Florent Corino	9/10	4923 days	1%
Amiot Cyriane	7/10	4923 days	1%
Annika	7/10	4923 days	1%
Jonas Herrmann	7/10	4923 days	1%
Matthieu Daveou	8/10	4923 days	1%
Julien Panossian	6/10	4923 days	1%
Raoul Montestruer	5/10	4923 days	0%
Alessa Ndra	8/10	4929 days	1%
Bjorn Hedmark	5/10	4930 days	0%
Evyatar Tulipman	7/10	4932 days	1%
S Curry	10/10	4947 days	1%
Ingrid	9/10	4991 days	1%
Reinier Timmer	7/10	4991 days	1%
Moorman	8/10	5000 days	1%
Stefan Roth	9/10	5025 days	1%
David	9/10	5039 days	1%
kevindang	10/10	5192 days	1%
Ruben Kunze	4/10	5274 days	0%
Sebastian Hol	9/10	5280 days	1%
Dick Stewart	8/10	5289 days	1%
David Beaumont	9/10	5296 days	1%
Beyeler	10/10	5301 days	1%
Nikita Sue	9/10	5306 days	1%
Schweiger	10/10	5308 days	1%
Jan & Marian	10/10	5387 days	1%
Konny	9/10	5391 days	1%
Waldemar Schuler	8/10	5391 days	1%
jule	3/10	5405 days	0%
Jack Potman	8/10	5607 days	1%
Jon_and_Family	9/10	5619 days	1%
Walker	9/10	5622 days	1%
Andreas Blessing	10/10	5630 days	1%
Gema	7/10	5633 days	1%
Avry Fabrice	6/10	5638 days	1%
Diane Johnston	9/10	5643 days	1%
Javier Munoz	8/10	5643 days	1%
Ben Akin-Smith	8/10	5644 days	1%
K Wallis	9/10	5649 days	1%
khs	9/10	5650 days	1%
Emma Ducat	9/10	5650 days	1%
Mr and Mrs Lambert	8/10	5657 days	1%
Andrew Koster	7/10	5663 days	1%
Bakker	8/10	5663 days	1%
Kimberly St Louis	8/10	5664 days	1%
Roel Wesstra	8/10	5670 days	1%
Seifert	10/10	5670 days	1%
Derek Woodward	9/10	5672 days	1%
Fabi & Sabi	8/10	5673 days	1%
Rosey834	8/10	5740 days	1%
Pete & Chris	10/10	5940 days	1%
Tony Masters	9/10	6003 days	1%
Hershell	8/10	6007 days	1%
Mike Robinson	9/10	6008 days	1%
Brent S	2/10	6009 days	0%
Zara Leyden	9/10	6017 days	1%
Judith	7/10	6021 days	1%
anon	8/10	6022 days	1%
Pierre Pilon	8/10	6023 days	1%
Jenny Omb	1/10	6028 days	0%
Frei Urs	6/10	6029 days	1%
Bryan Keddie	9/10	6039 days	1%
Leanne Rogan	5/10	6039 days	0%
Joanne Clarke	8/10	6043 days	1%
Wolfgang G	9/10	6049 days	1%
Thomas Signes	7/10	6070 days	1%
menzel	10/10	6088 days	1%
graemeh1	9/10	6089 days	1%
klinger	10/10	6089 days	1%
gereldineb	8/10	6099 days	1%
jennyb	9/10	6103 days	1%
Frank de Voogd	8/10	6109 days	1%
Jean Paul Mesnage	9/10	6115 days	1%
Hansjoerg Ehrmann	5/10	6116 days	0%
Daniel Alonso	9/10	6117 days	1%
Nigel Petrie	9/10	6128 days	1%
Tracy & Peter Cassidy	8/10	6144 days	1%
miniappleses	8/10	6166 days	1%
Josie Boyle	7/10	6277 days	1%
JanneP	9/10	6347 days	1%
Mikey	9/10	6354 days	1%
SablotniD	7/10	6359 days	1%
WiebkeS	9/10	6365 days	1%
Tanya	5/10	6367 days	0%
Jan	6/10	6367 days	1%
Viola	8/10	6369 days	1%
RowanL	7/10	6369 days	1%
VickiEngland	8/10	6377 days	1%
TomC1	8/10	6382 days	1%
AndyK	9/10	6382 days	1%
TatiamT	9/10	6382 days	1%
GillianK	8/10	6384 days	1%
EelcoK	9/10	6384 days	1%
Michael	9/10	6389 days	1%
soccaplaya14	10/10	6389 days	1%
Eugene	7/10	6391 days	1%
John	6/10	6393 days	1%
Tony	8/10	6398 days	1%
Middleton	4/10	6399 days	0%
Elise	8/10	6400 days	1%
Marie	8/10	6400 days	1%
ThomasS1	10/10	6404 days	1%
RasmusB	4/10	6406 days	0%
Simon	8/10	6412 days	1%
Phil&Joe	10/10	6414 days	1%
Marcus	7/10	6414 days	1%
Andre	7/10	6416 days	1%
Iris	9/10	6418 days	1%
Carla	7/10	6418 days	1%
Sandra	8/10	6422 days	1%
Schaffluber	10/10	6423 days	1%
Hayley	5/10	6424 days	0%
Con	2/10	6468 days	0%
felix	7/10	6469 days	1%
melissa	10/10	6475 days	1%
John B	5/10	6477 days	0%
Gemma	7/10	6516 days	1%
Henry	7/10	6517 days	1%
Antonella	10/10	6524 days	1%
Michelle	8/10	6524 days	1%
Laura	7/10	6533 days	1%
Sarah	8/10	6547 days	1%
Katerina	7/10	6568 days	1%
Erin	3/10	6568 days	0%
Mike Knight	9/10	6589 days	1%
Bronagh Mcartan	8/10	6598 days	1%
Dave	8/10	6609 days	1%
fgregory	10/10	6612 days	1%
Rhea	6/10	6657 days	1%
Georgina Mulligan	8/10	6669 days	1%
Karen C	7/10	6681 days	1%
Edmund Hillstone	10/10	6699 days	1%
Toby	6/10	6721 days	1%
Jennifer Baulch	9/10	6725 days	1%
Susan	8/10	6729 days	1%
Hoetnagels	7/10	6732 days	1%
Alan Bellerby	8/10	6735 days	1%
Sanne Jonker	7/10	6736 days	1%
Renske Tehurne	8/10	6740 days	1%
Benjamin Krein	7/10	6740 days	1%
Anne and Derek	8/10	6741 days	1%
James Davies	7/10	6741 days	1%
Naomi Horton	8/10	6742 days	1%
Roger Repolusk	8/10	6746 days	1%
Tony Wicks	6/10	6746 days	1%
Nancy Dol	8/10	6746 days	1%
Kristine	10/10	6746 days	1%
Kathy Hawey	9/10	6748 days	1%
David Buckley	8/10	6749 days	1%
Lena1	6/10	6750 days	1%
John Woodrow	8/10	6750 days	1%
Carmen Dolny	10/10	6750 days	1%
Haemnerli	8/10	6754 days	1%
Carla	8/10	6761 days	1%
Jim Curley	8/10	6761 days	1%
paulonline	7/10	6767 days	1%
Bex	6/10	6777 days	1%
Jenny Hulsebosch	8/10	6777 days	1%
Melissa Steedman	8/10	6788 days	1%
Tim	7/10	6789 days	1%
Falk Seidel	7/10	6792 days	1%
Hans Olthof	8/10	6792 days	1%
Anu	9/10	6795 days	1%
Anneli	6/10	6797 days	1%
purplekat99	10/10	6805 days	1%
Connor	10/10	6818 days	1%
Ad	7/10	6818 days	1%
Ann Westmacott	5/10	6823 days	0%
Paul Cowie	8/10	6824 days	1%
Ewen Maclean	8/10	6824 days	1%
Sarah Wilton	5/10	6824 days	0%
Arend v Dyn	7/10	6826 days	1%
Linda	8/10	6830 days	1%
Fiona	7/10	6830 days	1%
Ann	7/10	6831 days	1%
ranker_584	9/10	6834 days	1%
Christine	7/10	6834 days	1%
Nina	9/10	6834 days	1%
Anthony	7/10	6839 days	1%
Tom Clements	7/10	6839 days	1%
ranker_46	8/10	6951 days	1%
Pat Brewster	8/10	6951 days	1%
FrankOosterwijk	6/10	7036 days	1%
Kim	8/10	7036 days	1%
Helen	7/10	7067 days	1%
Heather	9/10	7067 days	1%
Helene	9/10	7079 days	1%
John	7/10	7079 days	1%
Giancarlo	6/10	7079 days	1%
Annette	4/10	7103 days	0%
John	5/10	7103 days	0%
Duncan	9/10	7108 days	1%
Jen	4/10	7119 days	0%
Rolf	8/10	7127 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

-1.76% Adjustment

There may be an adjustment if this experience hasn't received any reviews within the last 110 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 149 days. Adjustments are according to the following table.

Days	Adjustment
…	…
146	-1.72%
147	-1.74%
148	-1.75%
149	-1.76%
150	-1.77%
151	-1.78%
152	-1.80%
…	…

Balancing Adjustment

8.67% 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

76%

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.