Interislander Ferry

Ranking Score Explained

Hey, 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

351 Valid Reviews

The Interislander Ferry experience has a total of 362 reviews. There are 351 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 351 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	2	1%
1/10	5	1%

77.01% Average

The raw data average (mean) for all the Interislander Ferry valid reviews is 77.01% and is based on 351 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 351 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

73.85%

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
Ruban K	1/10	18 days	41%
Maria Longstaff	10/10	49 days	100%
Rina	9/10	171 days	97%
edm	1/10	445 days	36%
Colin Barrow	9/10	506 days	85%
Pauline	6/10	659 days	65%
Megan	5/10	811 days	48%
Marjolaine Loitz	4/10	841 days	39%
Keli Knox	10/10	1176 days	29%
Yar	1/10	1390 days	6%
Pinocity	6/10	1755 days	5%
Helen Russell	10/10	1936 days	5%
NewZealander	10/10	2210 days	4%
Tommy Pickett	9/10	3033 days	3%
Tom Bennett	8/10	3037 days	3%
Jeny Smolders	9/10	3039 days	3%
Gregg Wagstaff	7/10	3264 days	2%
Lianne Ijlst	8/10	3292 days	2%
Samantha and Neis	8/10	3293 days	2%
Brandon Cassidy	7/10	3309 days	2%
Vic Baughen	9/10	3311 days	2%
Anders Frank	7/10	3315 days	2%
Dina Schurer	8/10	3316 days	2%
Kim Youngsub	9/10	3317 days	2%
DEBBIE LAMBERT	10/10	3321 days	2%
Gary Williams	8/10	3321 days	2%
Kimberley Gardien	8/10	3328 days	2%
Antoine	9/10	3349 days	2%
Judit Van lanen	9/10	3354 days	2%
Bjorn Nielsen	8/10	3356 days	2%
Joel Virtanen	9/10	3358 days	2%
Corbin Hure	7/10	3358 days	2%
Ron	6/10	3361 days	2%
Thomas Simeon	8/10	3361 days	2%
Suzannah Hill	8/10	3362 days	2%
Kallan Mrozek	9/10	3363 days	2%
Kees Mol	9/10	3367 days	2%
Kristal Lavender	10/10	3367 days	2%
Bastian Bley	9/10	3368 days	2%
Jasmine Rogers	3/10	3369 days	1%
Louis Nilsson	8/10	3373 days	2%
Tim	7/10	3373 days	2%
Jendrik	6/10	3373 days	2%
Katharina	7/10	3374 days	2%
Chris Valchero	9/10	3377 days	2%
Rulp Niet	8/10	3379 days	2%
Soeren Buchheister	9/10	3380 days	2%
Chas Bronson	8/10	3380 days	2%
Jakob Lovdahl	9/10	3382 days	2%
Alexandra Schmidt	10/10	3392 days	2%
Jade Williams	10/10	3393 days	2%
Sam Staines	10/10	3394 days	2%
Nickolas Jonkergouw	7/10	3398 days	2%
Kirsty Smith	10/10	3398 days	2%
Eva Hesse	10/10	3413 days	2%
celine gries	8/10	3413 days	2%
tinagermany111	8/10	3428 days	2%
Cassandra Geyer	8/10	3612 days	1%
Olivier Reculeau	8/10	3613 days	1%
Thomas Michel	5/10	3614 days	1%
Lisa Haedrich	5/10	3618 days	1%
Nadja Guiliani	8/10	3622 days	1%
Elbrich	8/10	3622 days	1%
Jamie Serieux	7/10	3625 days	1%
Adele Jacques	9/10	3626 days	1%
Daniel Weber	6/10	3628 days	1%
Emily Noyd	8/10	3630 days	1%
Aparna Gula	10/10	3631 days	1%
Sebastiaan	7/10	3633 days	1%
Andre	9/10	3634 days	1%
Benedikt Hang	7/10	3635 days	1%
Yannick	8/10	3635 days	1%
S Black	9/10	3636 days	1%
Paul Larauze	6/10	3639 days	1%
Florence	6/10	3640 days	1%
Sarah Kovacs	8/10	3641 days	1%
Frenziska Schmid	7/10	3643 days	1%
Maud Livolsi	7/10	3650 days	1%
Lewis Whittle	6/10	3652 days	1%
Lukas Seager	6/10	3652 days	1%
Andrea Tabaka	8/10	3659 days	1%
Tina Rust	8/10	3661 days	1%
Joel Papak	8/10	3663 days	1%
Clemence and Pedro	9/10	3664 days	1%
Doms Wahlelr	9/10	3666 days	1%
Josef Biller	8/10	3666 days	1%
Justine Hoffmann	8/10	3667 days	1%
Friederike East	7/10	3667 days	1%
Mark White	10/10	3668 days	1%
Briony	8/10	3671 days	1%
Gabriel Siibers	8/10	3671 days	1%
Henry Wichler	8/10	3672 days	1%
Kyle Johnson	9/10	3674 days	1%
Niels Wezenberg	7/10	3675 days	1%
John Hamilton	9/10	3675 days	1%
Brianna Burd	9/10	3675 days	1%
Jessica Ruhland	8/10	3676 days	1%
Stula Vladimir	10/10	3677 days	1%
Cosmo Hartuna	7/10	3679 days	1%
Roland Fischer	6/10	3679 days	1%
Ross Holmes	9/10	3680 days	1%
Tilman	9/10	3682 days	1%
Petru	7/10	3683 days	1%
Fero Saarinen	6/10	3684 days	1%
Lauren Thompson	8/10	3686 days	1%
Meilin	8/10	3689 days	1%
Jonas Hoerning	10/10	3693 days	1%
Vanesha Patel	6/10	3694 days	1%
Mauricio Daniele	9/10	3694 days	1%
Sara and Antoine	8/10	3696 days	1%
Clare Pickford	6/10	3696 days	1%
Daniel Hill	10/10	3697 days	1%
Moritz Braun	7/10	3713 days	1%
Grischa Rodust	8/10	3720 days	1%
Chalie Dotesek	9/10	3721 days	1%
Julien Lafeville	7/10	3725 days	1%
Julia Huesam	8/10	3725 days	1%
Alexandre	9/10	3729 days	1%
Kev Zarka	6/10	3730 days	1%
Markus Wabing	8/10	3733 days	1%
Gessica	6/10	3766 days	1%
Simon Quass	9/10	3770 days	1%
Barthelemy	7/10	3999 days	1%
Brita Topp	10/10	4342 days	0%
Laim Thompson	8/10	4342 days	0%
Adriana	10/10	4350 days	0%
Pavel Jarolimek	5/10	4350 days	0%
Leonie Moeller	6/10	4351 days	0%
Doreen Gendel	8/10	4352 days	0%
Carla Oyarzun	3/10	4355 days	0%
Paolo Cases	3/10	4355 days	0%
Wolfgang and Christine	8/10	4360 days	0%
Helen	8/10	4373 days	0%
Olivier Carval	9/10	4375 days	0%
Hirsch Svenja	9/10	4376 days	0%
Mahr Svenja	8/10	4376 days	0%
Anna Guzewiez	9/10	4392 days	1%
Pier Durand	8/10	4396 days	1%
Serena Poggioli	9/10	4396 days	1%
Wayne Schist	7/10	4396 days	1%
Margreth Lydie	5/10	4404 days	1%
Laura Pleumeekers	7/10	4418 days	1%
David Brooks	10/10	4421 days	1%
Adrien Godeloup	9/10	4430 days	1%
Bet Dreno	8/10	4431 days	1%
Joachim	1/10	4432 days	0%
Pioter Jurkowski	7/10	4432 days	1%
Thomas Roche	9/10	4434 days	1%
Brian	9/10	4493 days	1%
hendrik king	9/10	4616 days	1%
Kiki Wykstra	5/10	4726 days	1%
Galen Licht	4/10	4726 days	1%
Yu-Ti Chu	7/10	4729 days	1%
Ton Martens	7/10	4729 days	1%
Joshua Perry	8/10	4734 days	1%
Molly Ladd	8/10	4734 days	1%
Michael Nolan	9/10	4738 days	1%
Julian Roots	9/10	4738 days	1%
Florent Corino	9/10	4742 days	1%
Amiot Cyriane	7/10	4742 days	1%
Annika	7/10	4742 days	1%
Jonas Herrmann	7/10	4742 days	1%
Matthieu Daveou	8/10	4742 days	1%
Julien Panossian	6/10	4742 days	1%
Raoul Montestruer	5/10	4742 days	1%
Alessa Ndra	8/10	4748 days	1%
Bjorn Hedmark	5/10	4749 days	1%
Evyatar Tulipman	7/10	4751 days	1%
S Curry	10/10	4766 days	1%
Ingrid	9/10	4810 days	1%
Reinier Timmer	7/10	4810 days	1%
Moorman	8/10	4819 days	1%
Stefan Roth	9/10	4844 days	1%
David	9/10	4858 days	1%
kevindang	10/10	5011 days	1%
Ruben Kunze	4/10	5093 days	1%
Sebastian Hol	9/10	5099 days	1%
Dick Stewart	8/10	5108 days	1%
David Beaumont	9/10	5115 days	1%
Beyeler	10/10	5120 days	1%
Nikita Sue	9/10	5125 days	1%
Schweiger	10/10	5127 days	1%
Jan & Marian	10/10	5206 days	1%
Konny	9/10	5210 days	1%
Waldemar Schuler	8/10	5210 days	1%
jule	3/10	5224 days	1%
Jack Potman	8/10	5426 days	1%
Jon_and_Family	9/10	5438 days	1%
Walker	9/10	5441 days	1%
Andreas Blessing	10/10	5449 days	1%
Gema	7/10	5452 days	1%
Avry Fabrice	6/10	5457 days	1%
Diane Johnston	9/10	5462 days	1%
Javier Munoz	8/10	5462 days	1%
Ben Akin-Smith	8/10	5463 days	1%
K Wallis	9/10	5468 days	1%
khs	9/10	5469 days	1%
Emma Ducat	9/10	5469 days	1%
Mr and Mrs Lambert	8/10	5476 days	1%
Andrew Koster	7/10	5482 days	1%
Bakker	8/10	5482 days	1%
Kimberly St Louis	8/10	5483 days	1%
Roel Wesstra	8/10	5489 days	1%
Seifert	10/10	5489 days	1%
Derek Woodward	9/10	5491 days	1%
Fabi & Sabi	8/10	5492 days	1%
Rosey834	8/10	5559 days	1%
Pete & Chris	10/10	5759 days	1%
Tony Masters	9/10	5822 days	1%
Hershell	8/10	5826 days	1%
Mike Robinson	9/10	5827 days	1%
Brent S	2/10	5828 days	0%
Zara Leyden	9/10	5836 days	1%
Judith	7/10	5840 days	1%
anon	8/10	5841 days	1%
Pierre Pilon	8/10	5842 days	1%
Jenny Omb	1/10	5847 days	0%
Frei Urs	6/10	5848 days	1%
Bryan Keddie	9/10	5858 days	1%
Leanne Rogan	5/10	5858 days	1%
Joanne Clarke	8/10	5862 days	1%
Wolfgang G	9/10	5868 days	1%
Thomas Signes	7/10	5889 days	1%
menzel	10/10	5907 days	1%
graemeh1	9/10	5908 days	1%
klinger	10/10	5908 days	1%
gereldineb	8/10	5918 days	1%
jennyb	9/10	5922 days	1%
Frank de Voogd	8/10	5928 days	1%
Jean Paul Mesnage	9/10	5934 days	1%
Hansjoerg Ehrmann	5/10	5935 days	1%
Daniel Alonso	9/10	5936 days	1%
Nigel Petrie	9/10	5947 days	1%
Tracy & Peter Cassidy	8/10	5963 days	1%
miniappleses	8/10	5985 days	1%
Josie Boyle	7/10	6096 days	1%
JanneP	9/10	6166 days	1%
Mikey	9/10	6173 days	1%
SablotniD	7/10	6178 days	1%
WiebkeS	9/10	6184 days	1%
Tanya	5/10	6185 days	1%
Jan	6/10	6186 days	1%
Viola	8/10	6187 days	1%
RowanL	7/10	6188 days	1%
VickiEngland	8/10	6196 days	1%
TomC1	8/10	6201 days	1%
AndyK	9/10	6201 days	1%
TatiamT	9/10	6201 days	1%
GillianK	8/10	6203 days	1%
EelcoK	9/10	6203 days	1%
Michael	9/10	6207 days	1%
soccaplaya14	10/10	6208 days	1%
Eugene	7/10	6209 days	1%
John	6/10	6211 days	1%
Tony	8/10	6216 days	1%
Middleton	4/10	6217 days	1%
Elise	8/10	6219 days	1%
Marie	8/10	6219 days	1%
ThomasS1	10/10	6223 days	1%
RasmusB	4/10	6225 days	1%
Simon	8/10	6230 days	1%
Phil&Joe	10/10	6232 days	1%
Marcus	7/10	6233 days	1%
Andre	7/10	6234 days	1%
Iris	9/10	6236 days	1%
Carla	7/10	6236 days	1%
Sandra	8/10	6240 days	1%
Schaffluber	10/10	6241 days	1%
Hayley	5/10	6242 days	1%
Con	2/10	6286 days	0%
felix	7/10	6287 days	1%
melissa	10/10	6294 days	1%
John B	5/10	6296 days	1%
Gemma	7/10	6335 days	1%
Henry	7/10	6335 days	1%
Antonella	10/10	6343 days	1%
Michelle	8/10	6343 days	1%
Laura	7/10	6351 days	1%
Sarah	8/10	6366 days	1%
Katerina	7/10	6386 days	1%
Erin	3/10	6386 days	1%
Mike Knight	9/10	6407 days	1%
Bronagh Mcartan	8/10	6416 days	1%
Dave	8/10	6427 days	1%
fgregory	10/10	6431 days	1%
Rhea	6/10	6476 days	1%
Georgina Mulligan	8/10	6488 days	1%
Karen C	7/10	6500 days	1%
Edmund Hillstone	10/10	6517 days	1%
Toby	6/10	6540 days	1%
Jennifer Baulch	9/10	6544 days	1%
Susan	8/10	6548 days	1%
Hoetnagels	7/10	6551 days	1%
Alan Bellerby	8/10	6554 days	1%
Sanne Jonker	7/10	6555 days	1%
Renske Tehurne	8/10	6559 days	1%
Benjamin Krein	7/10	6559 days	1%
Anne and Derek	8/10	6560 days	1%
James Davies	7/10	6560 days	1%
Naomi Horton	8/10	6561 days	1%
Roger Repolusk	8/10	6565 days	1%
Tony Wicks	6/10	6565 days	1%
Nancy Dol	8/10	6565 days	1%
Kristine	10/10	6565 days	1%
Kathy Hawey	9/10	6567 days	1%
David Buckley	8/10	6568 days	1%
Lena1	6/10	6568 days	1%
John Woodrow	8/10	6569 days	1%
Carmen Dolny	10/10	6569 days	1%
Haemnerli	8/10	6573 days	1%
Carla	8/10	6580 days	1%
Jim Curley	8/10	6580 days	1%
paulonline	7/10	6586 days	1%
Bex	6/10	6595 days	1%
Jenny Hulsebosch	8/10	6596 days	1%
Melissa Steedman	8/10	6607 days	1%
Tim	7/10	6608 days	1%
Falk Seidel	7/10	6611 days	1%
Hans Olthof	8/10	6611 days	1%
Anu	9/10	6614 days	1%
Anneli	6/10	6616 days	1%
purplekat99	10/10	6624 days	1%
Connor	10/10	6637 days	1%
Ad	7/10	6637 days	1%
Ann Westmacott	5/10	6642 days	1%
Paul Cowie	8/10	6643 days	1%
Ewen Maclean	8/10	6643 days	1%
Sarah Wilton	5/10	6643 days	1%
Arend v Dyn	7/10	6645 days	1%
Linda	8/10	6649 days	1%
Fiona	7/10	6649 days	1%
Ann	7/10	6650 days	1%
ranker_584	9/10	6653 days	1%
Christine	7/10	6653 days	1%
Nina	9/10	6653 days	1%
Anthony	7/10	6658 days	1%
Tom Clements	7/10	6658 days	1%
ranker_46	8/10	6770 days	1%
Pat Brewster	8/10	6770 days	1%
FrankOosterwijk	6/10	6855 days	1%
Kim	8/10	6855 days	1%
Helen	7/10	6886 days	1%
Heather	9/10	6886 days	1%
Helene	9/10	6898 days	1%
John	7/10	6898 days	1%
Giancarlo	6/10	6898 days	1%
Annette	4/10	6922 days	1%
John	5/10	6922 days	1%
Duncan	9/10	6927 days	1%
Jen	4/10	6938 days	1%
Rolf	8/10	6946 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

-0.33% Adjustment

There may be an adjustment if this experience hasn't received any reviews within the last 53 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 16 days. Adjustments are according to the following table.

Days	Adjustment
…	…
13	-0.27%
14	-0.29%
15	-0.31%
16	-0.33%
17	-0.35%
18	-0.37%
19	-0.39%
…	…

Balancing Adjustment

5.26% 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

79%

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.