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

69.02%

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	191 days	46%
Nico	1/10	191 days	41%
Ruban K	1/10	219 days	41%
Maria Longstaff	10/10	250 days	100%
Rina	9/10	372 days	95%
edm	1/10	646 days	32%
Colin Barrow	9/10	707 days	73%
Pauline	6/10	860 days	51%
Megan	5/10	1012 days	34%
Marjolaine Loitz	4/10	1042 days	27%
Keli Knox	10/10	1377 days	17%
Yar	1/10	1591 days	3%
Pinocity	6/10	1956 days	4%
Helen Russell	10/10	2137 days	4%
NewZealander	10/10	2411 days	4%
Tommy Pickett	9/10	3234 days	2%
Tom Bennett	8/10	3238 days	2%
Jeny Smolders	9/10	3240 days	2%
Gregg Wagstaff	7/10	3465 days	1%
Lianne Ijlst	8/10	3493 days	1%
Samantha and Neis	8/10	3494 days	1%
Brandon Cassidy	7/10	3510 days	1%
Vic Baughen	9/10	3512 days	1%
Anders Frank	7/10	3516 days	1%
Dina Schurer	8/10	3517 days	1%
Kim Youngsub	9/10	3518 days	1%
DEBBIE LAMBERT	10/10	3522 days	1%
Gary Williams	8/10	3522 days	1%
Kimberley Gardien	8/10	3529 days	1%
Antoine	9/10	3550 days	1%
Judit Van lanen	9/10	3555 days	1%
Bjorn Nielsen	8/10	3557 days	1%
Joel Virtanen	9/10	3559 days	1%
Corbin Hure	7/10	3559 days	1%
Ron	6/10	3562 days	1%
Thomas Simeon	8/10	3562 days	1%
Suzannah Hill	8/10	3563 days	1%
Kallan Mrozek	9/10	3564 days	1%
Kees Mol	9/10	3568 days	1%
Kristal Lavender	10/10	3568 days	1%
Bastian Bley	9/10	3569 days	1%
Jasmine Rogers	3/10	3570 days	1%
Louis Nilsson	8/10	3574 days	1%
Tim	7/10	3574 days	1%
Jendrik	6/10	3574 days	1%
Katharina	7/10	3575 days	1%
Chris Valchero	9/10	3578 days	1%
Rulp Niet	8/10	3580 days	1%
Soeren Buchheister	9/10	3581 days	1%
Chas Bronson	8/10	3581 days	1%
Jakob Lovdahl	9/10	3583 days	1%
Alexandra Schmidt	10/10	3593 days	1%
Jade Williams	10/10	3594 days	1%
Sam Staines	10/10	3595 days	1%
Nickolas Jonkergouw	7/10	3599 days	1%
Kirsty Smith	10/10	3599 days	1%
Eva Hesse	10/10	3614 days	1%
celine gries	8/10	3614 days	1%
tinagermany111	8/10	3628 days	1%
Cassandra Geyer	8/10	3813 days	1%
Olivier Reculeau	8/10	3814 days	1%
Thomas Michel	5/10	3815 days	1%
Lisa Haedrich	5/10	3819 days	1%
Nadja Guiliani	8/10	3823 days	1%
Elbrich	8/10	3823 days	1%
Jamie Serieux	7/10	3826 days	1%
Adele Jacques	9/10	3827 days	1%
Daniel Weber	6/10	3829 days	1%
Emily Noyd	8/10	3831 days	1%
Aparna Gula	10/10	3832 days	1%
Sebastiaan	7/10	3834 days	1%
Andre	9/10	3835 days	1%
Benedikt Hang	7/10	3836 days	1%
Yannick	8/10	3836 days	1%
S Black	9/10	3837 days	1%
Paul Larauze	6/10	3840 days	1%
Florence	6/10	3841 days	1%
Sarah Kovacs	8/10	3842 days	1%
Frenziska Schmid	7/10	3844 days	1%
Maud Livolsi	7/10	3851 days	1%
Lewis Whittle	6/10	3853 days	1%
Lukas Seager	6/10	3853 days	1%
Andrea Tabaka	8/10	3860 days	1%
Tina Rust	8/10	3862 days	1%
Joel Papak	8/10	3864 days	1%
Clemence and Pedro	9/10	3865 days	1%
Doms Wahlelr	9/10	3867 days	1%
Josef Biller	8/10	3867 days	1%
Justine Hoffmann	8/10	3868 days	1%
Friederike East	7/10	3868 days	1%
Mark White	10/10	3869 days	1%
Briony	8/10	3872 days	1%
Gabriel Siibers	8/10	3872 days	1%
Henry Wichler	8/10	3873 days	1%
Kyle Johnson	9/10	3875 days	1%
Niels Wezenberg	7/10	3876 days	1%
John Hamilton	9/10	3876 days	1%
Brianna Burd	9/10	3876 days	1%
Jessica Ruhland	8/10	3877 days	1%
Stula Vladimir	10/10	3878 days	1%
Cosmo Hartuna	7/10	3880 days	1%
Roland Fischer	6/10	3880 days	1%
Ross Holmes	9/10	3881 days	1%
Tilman	9/10	3883 days	1%
Petru	7/10	3884 days	1%
Fero Saarinen	6/10	3885 days	1%
Lauren Thompson	8/10	3887 days	1%
Meilin	8/10	3890 days	1%
Jonas Hoerning	10/10	3894 days	1%
Vanesha Patel	6/10	3895 days	1%
Mauricio Daniele	9/10	3895 days	1%
Sara and Antoine	8/10	3897 days	1%
Clare Pickford	6/10	3897 days	1%
Daniel Hill	10/10	3898 days	1%
Moritz Braun	7/10	3914 days	1%
Grischa Rodust	8/10	3921 days	1%
Chalie Dotesek	9/10	3922 days	1%
Julien Lafeville	7/10	3926 days	1%
Julia Huesam	8/10	3926 days	1%
Alexandre	9/10	3930 days	1%
Kev Zarka	6/10	3931 days	0%
Markus Wabing	8/10	3934 days	1%
Gessica	6/10	3967 days	0%
Simon Quass	9/10	3971 days	0%
Barthelemy	7/10	4200 days	0%
Brita Topp	10/10	4543 days	1%
Laim Thompson	8/10	4543 days	1%
Adriana	10/10	4551 days	1%
Pavel Jarolimek	5/10	4551 days	0%
Leonie Moeller	6/10	4552 days	1%
Doreen Gendel	8/10	4553 days	1%
Carla Oyarzun	3/10	4556 days	0%
Paolo Cases	3/10	4556 days	0%
Wolfgang and Christine	8/10	4561 days	1%
Helen	8/10	4574 days	1%
Olivier Carval	9/10	4576 days	1%
Hirsch Svenja	9/10	4577 days	1%
Mahr Svenja	8/10	4577 days	1%
Anna Guzewiez	9/10	4593 days	1%
Pier Durand	8/10	4597 days	1%
Serena Poggioli	9/10	4597 days	1%
Wayne Schist	7/10	4597 days	1%
Margreth Lydie	5/10	4605 days	0%
Laura Pleumeekers	7/10	4619 days	1%
David Brooks	10/10	4622 days	1%
Adrien Godeloup	9/10	4631 days	1%
Bet Dreno	8/10	4632 days	1%
Joachim	1/10	4633 days	0%
Pioter Jurkowski	7/10	4633 days	1%
Thomas Roche	9/10	4635 days	1%
Brian	9/10	4694 days	1%
hendrik king	9/10	4817 days	1%
Kiki Wykstra	5/10	4927 days	0%
Galen Licht	4/10	4927 days	0%
Yu-Ti Chu	7/10	4930 days	1%
Ton Martens	7/10	4930 days	1%
Joshua Perry	8/10	4935 days	1%
Molly Ladd	8/10	4935 days	1%
Michael Nolan	9/10	4939 days	1%
Julian Roots	9/10	4939 days	1%
Florent Corino	9/10	4943 days	1%
Amiot Cyriane	7/10	4943 days	1%
Annika	7/10	4943 days	1%
Jonas Herrmann	7/10	4943 days	1%
Matthieu Daveou	8/10	4943 days	1%
Julien Panossian	6/10	4943 days	1%
Raoul Montestruer	5/10	4943 days	0%
Alessa Ndra	8/10	4949 days	1%
Bjorn Hedmark	5/10	4950 days	0%
Evyatar Tulipman	7/10	4952 days	1%
S Curry	10/10	4967 days	1%
Ingrid	9/10	5011 days	1%
Reinier Timmer	7/10	5011 days	1%
Moorman	8/10	5020 days	1%
Stefan Roth	9/10	5045 days	1%
David	9/10	5059 days	1%
kevindang	10/10	5212 days	1%
Ruben Kunze	4/10	5294 days	0%
Sebastian Hol	9/10	5300 days	1%
Dick Stewart	8/10	5309 days	1%
David Beaumont	9/10	5316 days	1%
Beyeler	10/10	5321 days	1%
Nikita Sue	9/10	5326 days	1%
Schweiger	10/10	5328 days	1%
Jan & Marian	10/10	5407 days	1%
Konny	9/10	5411 days	1%
Waldemar Schuler	8/10	5411 days	1%
jule	3/10	5425 days	0%
Jack Potman	8/10	5627 days	1%
Jon_and_Family	9/10	5639 days	1%
Walker	9/10	5642 days	1%
Andreas Blessing	10/10	5650 days	1%
Gema	7/10	5653 days	1%
Avry Fabrice	6/10	5658 days	1%
Diane Johnston	9/10	5663 days	1%
Javier Munoz	8/10	5663 days	1%
Ben Akin-Smith	8/10	5664 days	1%
K Wallis	9/10	5669 days	1%
khs	9/10	5670 days	1%
Emma Ducat	9/10	5670 days	1%
Mr and Mrs Lambert	8/10	5677 days	1%
Andrew Koster	7/10	5683 days	1%
Bakker	8/10	5683 days	1%
Kimberly St Louis	8/10	5684 days	1%
Roel Wesstra	8/10	5690 days	1%
Seifert	10/10	5690 days	1%
Derek Woodward	9/10	5692 days	1%
Fabi & Sabi	8/10	5693 days	1%
Rosey834	8/10	5760 days	1%
Pete & Chris	10/10	5960 days	1%
Tony Masters	9/10	6023 days	1%
Hershell	8/10	6027 days	1%
Mike Robinson	9/10	6028 days	1%
Brent S	2/10	6029 days	0%
Zara Leyden	9/10	6037 days	1%
Judith	7/10	6041 days	1%
anon	8/10	6042 days	1%
Pierre Pilon	8/10	6043 days	1%
Jenny Omb	1/10	6048 days	0%
Frei Urs	6/10	6049 days	1%
Bryan Keddie	9/10	6059 days	1%
Leanne Rogan	5/10	6059 days	0%
Joanne Clarke	8/10	6063 days	1%
Wolfgang G	9/10	6069 days	1%
Thomas Signes	7/10	6090 days	1%
menzel	10/10	6108 days	1%
graemeh1	9/10	6109 days	1%
klinger	10/10	6109 days	1%
gereldineb	8/10	6119 days	1%
jennyb	9/10	6123 days	1%
Frank de Voogd	8/10	6129 days	1%
Jean Paul Mesnage	9/10	6135 days	1%
Hansjoerg Ehrmann	5/10	6136 days	0%
Daniel Alonso	9/10	6137 days	1%
Nigel Petrie	9/10	6148 days	1%
Tracy & Peter Cassidy	8/10	6164 days	1%
miniappleses	8/10	6186 days	1%
Josie Boyle	7/10	6297 days	1%
JanneP	9/10	6367 days	1%
Mikey	9/10	6374 days	1%
SablotniD	7/10	6378 days	1%
WiebkeS	9/10	6385 days	1%
Tanya	5/10	6386 days	0%
Jan	6/10	6386 days	1%
Viola	8/10	6388 days	1%
RowanL	7/10	6389 days	1%
VickiEngland	8/10	6397 days	1%
TomC1	8/10	6402 days	1%
AndyK	9/10	6402 days	1%
TatiamT	9/10	6402 days	1%
GillianK	8/10	6404 days	1%
EelcoK	9/10	6404 days	1%
Michael	9/10	6408 days	1%
soccaplaya14	10/10	6409 days	1%
Eugene	7/10	6410 days	1%
John	6/10	6412 days	1%
Tony	8/10	6417 days	1%
Middleton	4/10	6418 days	0%
Elise	8/10	6419 days	1%
Marie	8/10	6419 days	1%
ThomasS1	10/10	6424 days	1%
RasmusB	4/10	6426 days	0%
Simon	8/10	6431 days	1%
Phil&Joe	10/10	6433 days	1%
Marcus	7/10	6433 days	1%
Andre	7/10	6435 days	1%
Iris	9/10	6437 days	1%
Carla	7/10	6437 days	1%
Sandra	8/10	6441 days	1%
Schaffluber	10/10	6442 days	1%
Hayley	5/10	6443 days	0%
Con	2/10	6487 days	0%
felix	7/10	6488 days	1%
melissa	10/10	6495 days	1%
John B	5/10	6497 days	0%
Gemma	7/10	6536 days	1%
Henry	7/10	6536 days	1%
Antonella	10/10	6543 days	1%
Michelle	8/10	6543 days	1%
Laura	7/10	6552 days	1%
Sarah	8/10	6566 days	1%
Katerina	7/10	6587 days	1%
Erin	3/10	6587 days	0%
Mike Knight	9/10	6608 days	1%
Bronagh Mcartan	8/10	6617 days	1%
Dave	8/10	6628 days	1%
fgregory	10/10	6631 days	1%
Rhea	6/10	6677 days	1%
Georgina Mulligan	8/10	6689 days	1%
Karen C	7/10	6701 days	1%
Edmund Hillstone	10/10	6718 days	1%
Toby	6/10	6741 days	1%
Jennifer Baulch	9/10	6745 days	1%
Susan	8/10	6749 days	1%
Hoetnagels	7/10	6752 days	1%
Alan Bellerby	8/10	6755 days	1%
Sanne Jonker	7/10	6756 days	1%
Renske Tehurne	8/10	6760 days	1%
Benjamin Krein	7/10	6760 days	1%
Anne and Derek	8/10	6761 days	1%
James Davies	7/10	6761 days	1%
Naomi Horton	8/10	6762 days	1%
Roger Repolusk	8/10	6766 days	1%
Tony Wicks	6/10	6766 days	1%
Nancy Dol	8/10	6766 days	1%
Kristine	10/10	6766 days	1%
Kathy Hawey	9/10	6768 days	1%
David Buckley	8/10	6769 days	1%
Lena1	6/10	6769 days	1%
John Woodrow	8/10	6770 days	1%
Carmen Dolny	10/10	6770 days	1%
Haemnerli	8/10	6774 days	1%
Carla	8/10	6781 days	1%
Jim Curley	8/10	6781 days	1%
paulonline	7/10	6787 days	1%
Bex	6/10	6796 days	1%
Jenny Hulsebosch	8/10	6797 days	1%
Melissa Steedman	8/10	6808 days	1%
Tim	7/10	6809 days	1%
Falk Seidel	7/10	6812 days	1%
Hans Olthof	8/10	6812 days	1%
Anu	9/10	6815 days	1%
Anneli	6/10	6817 days	1%
purplekat99	10/10	6825 days	1%
Connor	10/10	6838 days	1%
Ad	7/10	6838 days	1%
Ann Westmacott	5/10	6843 days	0%
Paul Cowie	8/10	6844 days	1%
Ewen Maclean	8/10	6844 days	1%
Sarah Wilton	5/10	6844 days	0%
Arend v Dyn	7/10	6846 days	1%
Linda	8/10	6850 days	1%
Fiona	7/10	6850 days	1%
Ann	7/10	6851 days	1%
ranker_584	9/10	6854 days	1%
Christine	7/10	6854 days	1%
Nina	9/10	6854 days	1%
Anthony	7/10	6859 days	1%
Tom Clements	7/10	6859 days	1%
ranker_46	8/10	6971 days	1%
Pat Brewster	8/10	6971 days	1%
FrankOosterwijk	6/10	7056 days	1%
Kim	8/10	7056 days	1%
Helen	7/10	7087 days	1%
Heather	9/10	7087 days	1%
Helene	9/10	7099 days	1%
John	7/10	7099 days	1%
Giancarlo	6/10	7099 days	1%
Annette	4/10	7123 days	0%
John	5/10	7123 days	0%
Duncan	9/10	7128 days	1%
Jen	4/10	7139 days	0%
Rolf	8/10	7147 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

-2.33% Adjustment

There may be an adjustment if this experience hasn't received any reviews within the last 86 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 169 days. Adjustments are according to the following table.

Days	Adjustment
…	…
166	-2.29%
167	-2.31%
168	-2.32%
169	-2.33%
170	-2.35%
171	-2.36%
172	-2.38%
…	…

Balancing Adjustment

9.04% 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.