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

69.03%

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	212 days	46%
Nico	1/10	212 days	41%
Ruban K	1/10	240 days	41%
Maria Longstaff	10/10	271 days	100%
Rina	9/10	393 days	94%
edm	1/10	667 days	31%
Colin Barrow	9/10	728 days	72%
Pauline	6/10	881 days	50%
Megan	5/10	1033 days	32%
Marjolaine Loitz	4/10	1063 days	26%
Keli Knox	10/10	1398 days	16%
Yar	1/10	1612 days	3%
Pinocity	6/10	1977 days	4%
Helen Russell	10/10	2158 days	4%
NewZealander	10/10	2432 days	4%
Tommy Pickett	9/10	3255 days	2%
Tom Bennett	8/10	3259 days	2%
Jeny Smolders	9/10	3261 days	2%
Gregg Wagstaff	7/10	3486 days	1%
Lianne Ijlst	8/10	3514 days	1%
Samantha and Neis	8/10	3515 days	1%
Brandon Cassidy	7/10	3531 days	1%
Vic Baughen	9/10	3533 days	1%
Anders Frank	7/10	3537 days	1%
Dina Schurer	8/10	3538 days	1%
Kim Youngsub	9/10	3539 days	1%
DEBBIE LAMBERT	10/10	3543 days	1%
Gary Williams	8/10	3543 days	1%
Kimberley Gardien	8/10	3550 days	1%
Antoine	9/10	3571 days	1%
Judit Van lanen	9/10	3576 days	1%
Bjorn Nielsen	8/10	3578 days	1%
Joel Virtanen	9/10	3580 days	1%
Corbin Hure	7/10	3580 days	1%
Ron	6/10	3583 days	1%
Thomas Simeon	8/10	3583 days	1%
Suzannah Hill	8/10	3584 days	1%
Kallan Mrozek	9/10	3585 days	1%
Kees Mol	9/10	3589 days	1%
Kristal Lavender	10/10	3589 days	1%
Bastian Bley	9/10	3590 days	1%
Jasmine Rogers	3/10	3591 days	1%
Louis Nilsson	8/10	3595 days	1%
Tim	7/10	3595 days	1%
Jendrik	6/10	3595 days	1%
Katharina	7/10	3596 days	1%
Chris Valchero	9/10	3599 days	1%
Rulp Niet	8/10	3601 days	1%
Soeren Buchheister	9/10	3602 days	1%
Chas Bronson	8/10	3602 days	1%
Jakob Lovdahl	9/10	3604 days	1%
Alexandra Schmidt	10/10	3614 days	1%
Jade Williams	10/10	3615 days	1%
Sam Staines	10/10	3616 days	1%
Nickolas Jonkergouw	7/10	3620 days	1%
Kirsty Smith	10/10	3620 days	1%
Eva Hesse	10/10	3635 days	1%
celine gries	8/10	3635 days	1%
tinagermany111	8/10	3649 days	1%
Cassandra Geyer	8/10	3834 days	1%
Olivier Reculeau	8/10	3835 days	1%
Thomas Michel	5/10	3836 days	1%
Lisa Haedrich	5/10	3840 days	1%
Nadja Guiliani	8/10	3844 days	1%
Elbrich	8/10	3844 days	1%
Jamie Serieux	7/10	3847 days	1%
Adele Jacques	9/10	3848 days	1%
Daniel Weber	6/10	3850 days	1%
Emily Noyd	8/10	3852 days	1%
Aparna Gula	10/10	3853 days	1%
Sebastiaan	7/10	3855 days	1%
Andre	9/10	3856 days	1%
Benedikt Hang	7/10	3857 days	1%
Yannick	8/10	3857 days	1%
S Black	9/10	3858 days	1%
Paul Larauze	6/10	3861 days	1%
Florence	6/10	3862 days	1%
Sarah Kovacs	8/10	3863 days	1%
Frenziska Schmid	7/10	3865 days	1%
Maud Livolsi	7/10	3872 days	1%
Lewis Whittle	6/10	3874 days	1%
Lukas Seager	6/10	3874 days	1%
Andrea Tabaka	8/10	3881 days	1%
Tina Rust	8/10	3883 days	1%
Joel Papak	8/10	3885 days	1%
Clemence and Pedro	9/10	3886 days	1%
Doms Wahlelr	9/10	3888 days	1%
Josef Biller	8/10	3888 days	1%
Justine Hoffmann	8/10	3889 days	1%
Friederike East	7/10	3889 days	1%
Mark White	10/10	3890 days	1%
Briony	8/10	3893 days	1%
Gabriel Siibers	8/10	3893 days	1%
Henry Wichler	8/10	3894 days	1%
Kyle Johnson	9/10	3896 days	1%
Niels Wezenberg	7/10	3897 days	1%
John Hamilton	9/10	3897 days	1%
Brianna Burd	9/10	3897 days	1%
Jessica Ruhland	8/10	3898 days	1%
Stula Vladimir	10/10	3899 days	1%
Cosmo Hartuna	7/10	3901 days	1%
Roland Fischer	6/10	3901 days	1%
Ross Holmes	9/10	3902 days	1%
Tilman	9/10	3904 days	1%
Petru	7/10	3905 days	1%
Fero Saarinen	6/10	3906 days	1%
Lauren Thompson	8/10	3908 days	1%
Meilin	8/10	3911 days	1%
Jonas Hoerning	10/10	3915 days	1%
Vanesha Patel	6/10	3916 days	1%
Mauricio Daniele	9/10	3916 days	1%
Sara and Antoine	8/10	3918 days	1%
Clare Pickford	6/10	3918 days	1%
Daniel Hill	10/10	3919 days	1%
Moritz Braun	7/10	3935 days	1%
Grischa Rodust	8/10	3942 days	1%
Chalie Dotesek	9/10	3943 days	1%
Julien Lafeville	7/10	3947 days	1%
Julia Huesam	8/10	3947 days	1%
Alexandre	9/10	3951 days	1%
Kev Zarka	6/10	3952 days	0%
Markus Wabing	8/10	3955 days	1%
Gessica	6/10	3988 days	0%
Simon Quass	9/10	3992 days	0%
Barthelemy	7/10	4221 days	0%
Brita Topp	10/10	4564 days	1%
Laim Thompson	8/10	4564 days	1%
Adriana	10/10	4572 days	1%
Pavel Jarolimek	5/10	4572 days	0%
Leonie Moeller	6/10	4573 days	1%
Doreen Gendel	8/10	4574 days	1%
Carla Oyarzun	3/10	4577 days	0%
Paolo Cases	3/10	4577 days	0%
Wolfgang and Christine	8/10	4582 days	1%
Helen	8/10	4595 days	1%
Olivier Carval	9/10	4597 days	1%
Hirsch Svenja	9/10	4598 days	1%
Mahr Svenja	8/10	4598 days	1%
Anna Guzewiez	9/10	4614 days	1%
Pier Durand	8/10	4618 days	1%
Serena Poggioli	9/10	4618 days	1%
Wayne Schist	7/10	4618 days	1%
Margreth Lydie	5/10	4626 days	0%
Laura Pleumeekers	7/10	4640 days	1%
David Brooks	10/10	4643 days	1%
Adrien Godeloup	9/10	4652 days	1%
Bet Dreno	8/10	4653 days	1%
Joachim	1/10	4654 days	0%
Pioter Jurkowski	7/10	4654 days	1%
Thomas Roche	9/10	4656 days	1%
Brian	9/10	4715 days	1%
hendrik king	9/10	4838 days	1%
Kiki Wykstra	5/10	4948 days	0%
Galen Licht	4/10	4948 days	0%
Yu-Ti Chu	7/10	4951 days	1%
Ton Martens	7/10	4951 days	1%
Joshua Perry	8/10	4956 days	1%
Molly Ladd	8/10	4956 days	1%
Michael Nolan	9/10	4960 days	1%
Julian Roots	9/10	4960 days	1%
Florent Corino	9/10	4964 days	1%
Amiot Cyriane	7/10	4964 days	1%
Annika	7/10	4964 days	1%
Jonas Herrmann	7/10	4964 days	1%
Matthieu Daveou	8/10	4964 days	1%
Julien Panossian	6/10	4964 days	1%
Raoul Montestruer	5/10	4964 days	0%
Alessa Ndra	8/10	4970 days	1%
Bjorn Hedmark	5/10	4971 days	0%
Evyatar Tulipman	7/10	4973 days	1%
S Curry	10/10	4988 days	1%
Ingrid	9/10	5032 days	1%
Reinier Timmer	7/10	5032 days	1%
Moorman	8/10	5041 days	1%
Stefan Roth	9/10	5066 days	1%
David	9/10	5080 days	1%
kevindang	10/10	5233 days	1%
Ruben Kunze	4/10	5315 days	0%
Sebastian Hol	9/10	5321 days	1%
Dick Stewart	8/10	5330 days	1%
David Beaumont	9/10	5337 days	1%
Beyeler	10/10	5342 days	1%
Nikita Sue	9/10	5347 days	1%
Schweiger	10/10	5349 days	1%
Jan & Marian	10/10	5428 days	1%
Konny	9/10	5432 days	1%
Waldemar Schuler	8/10	5432 days	1%
jule	3/10	5446 days	0%
Jack Potman	8/10	5648 days	1%
Jon_and_Family	9/10	5660 days	1%
Walker	9/10	5663 days	1%
Andreas Blessing	10/10	5671 days	1%
Gema	7/10	5674 days	1%
Avry Fabrice	6/10	5679 days	1%
Diane Johnston	9/10	5684 days	1%
Javier Munoz	8/10	5684 days	1%
Ben Akin-Smith	8/10	5685 days	1%
K Wallis	9/10	5690 days	1%
khs	9/10	5691 days	1%
Emma Ducat	9/10	5691 days	1%
Mr and Mrs Lambert	8/10	5698 days	1%
Andrew Koster	7/10	5704 days	1%
Bakker	8/10	5704 days	1%
Kimberly St Louis	8/10	5705 days	1%
Roel Wesstra	8/10	5711 days	1%
Seifert	10/10	5711 days	1%
Derek Woodward	9/10	5713 days	1%
Fabi & Sabi	8/10	5714 days	1%
Rosey834	8/10	5781 days	1%
Pete & Chris	10/10	5981 days	1%
Tony Masters	9/10	6044 days	1%
Hershell	8/10	6048 days	1%
Mike Robinson	9/10	6049 days	1%
Brent S	2/10	6050 days	0%
Zara Leyden	9/10	6058 days	1%
Judith	7/10	6062 days	1%
anon	8/10	6063 days	1%
Pierre Pilon	8/10	6064 days	1%
Jenny Omb	1/10	6069 days	0%
Frei Urs	6/10	6070 days	1%
Bryan Keddie	9/10	6080 days	1%
Leanne Rogan	5/10	6080 days	0%
Joanne Clarke	8/10	6084 days	1%
Wolfgang G	9/10	6090 days	1%
Thomas Signes	7/10	6111 days	1%
menzel	10/10	6129 days	1%
graemeh1	9/10	6130 days	1%
klinger	10/10	6130 days	1%
gereldineb	8/10	6140 days	1%
jennyb	9/10	6144 days	1%
Frank de Voogd	8/10	6150 days	1%
Jean Paul Mesnage	9/10	6156 days	1%
Hansjoerg Ehrmann	5/10	6157 days	0%
Daniel Alonso	9/10	6158 days	1%
Nigel Petrie	9/10	6169 days	1%
Tracy & Peter Cassidy	8/10	6185 days	1%
miniappleses	8/10	6207 days	1%
Josie Boyle	7/10	6318 days	1%
JanneP	9/10	6388 days	1%
Mikey	9/10	6395 days	1%
SablotniD	7/10	6399 days	1%
WiebkeS	9/10	6406 days	1%
Tanya	5/10	6407 days	0%
Jan	6/10	6407 days	1%
Viola	8/10	6409 days	1%
RowanL	7/10	6410 days	1%
VickiEngland	8/10	6418 days	1%
TomC1	8/10	6423 days	1%
AndyK	9/10	6423 days	1%
TatiamT	9/10	6423 days	1%
GillianK	8/10	6425 days	1%
EelcoK	9/10	6425 days	1%
Michael	9/10	6429 days	1%
soccaplaya14	10/10	6430 days	1%
Eugene	7/10	6431 days	1%
John	6/10	6433 days	1%
Tony	8/10	6438 days	1%
Middleton	4/10	6439 days	0%
Elise	8/10	6440 days	1%
Marie	8/10	6440 days	1%
ThomasS1	10/10	6445 days	1%
RasmusB	4/10	6447 days	0%
Simon	8/10	6452 days	1%
Phil&Joe	10/10	6454 days	1%
Marcus	7/10	6454 days	1%
Andre	7/10	6456 days	1%
Iris	9/10	6458 days	1%
Carla	7/10	6458 days	1%
Sandra	8/10	6462 days	1%
Schaffluber	10/10	6463 days	1%
Hayley	5/10	6464 days	0%
Con	2/10	6508 days	0%
felix	7/10	6509 days	1%
melissa	10/10	6515 days	1%
John B	5/10	6518 days	0%
Gemma	7/10	6556 days	1%
Henry	7/10	6557 days	1%
Antonella	10/10	6564 days	1%
Michelle	8/10	6564 days	1%
Laura	7/10	6573 days	1%
Sarah	8/10	6587 days	1%
Katerina	7/10	6608 days	1%
Erin	3/10	6608 days	0%
Mike Knight	9/10	6629 days	1%
Bronagh Mcartan	8/10	6638 days	1%
Dave	8/10	6649 days	1%
fgregory	10/10	6652 days	1%
Rhea	6/10	6698 days	1%
Georgina Mulligan	8/10	6710 days	1%
Karen C	7/10	6722 days	1%
Edmund Hillstone	10/10	6739 days	1%
Toby	6/10	6762 days	1%
Jennifer Baulch	9/10	6766 days	1%
Susan	8/10	6770 days	1%
Hoetnagels	7/10	6773 days	1%
Alan Bellerby	8/10	6776 days	1%
Sanne Jonker	7/10	6777 days	1%
Renske Tehurne	8/10	6781 days	1%
Benjamin Krein	7/10	6781 days	1%
Anne and Derek	8/10	6782 days	1%
James Davies	7/10	6782 days	1%
Naomi Horton	8/10	6783 days	1%
Roger Repolusk	8/10	6787 days	1%
Tony Wicks	6/10	6787 days	1%
Nancy Dol	8/10	6787 days	1%
Kristine	10/10	6787 days	1%
Kathy Hawey	9/10	6789 days	1%
David Buckley	8/10	6790 days	1%
Lena1	6/10	6790 days	1%
John Woodrow	8/10	6791 days	1%
Carmen Dolny	10/10	6791 days	1%
Haemnerli	8/10	6795 days	1%
Carla	8/10	6802 days	1%
Jim Curley	8/10	6802 days	1%
paulonline	7/10	6808 days	1%
Bex	6/10	6817 days	1%
Jenny Hulsebosch	8/10	6818 days	1%
Melissa Steedman	8/10	6829 days	1%
Tim	7/10	6830 days	1%
Falk Seidel	7/10	6833 days	1%
Hans Olthof	8/10	6833 days	1%
Anu	9/10	6836 days	1%
Anneli	6/10	6838 days	1%
purplekat99	10/10	6846 days	1%
Connor	10/10	6859 days	1%
Ad	7/10	6859 days	1%
Ann Westmacott	5/10	6864 days	0%
Paul Cowie	8/10	6865 days	1%
Ewen Maclean	8/10	6865 days	1%
Sarah Wilton	5/10	6865 days	0%
Arend v Dyn	7/10	6867 days	1%
Linda	8/10	6871 days	1%
Fiona	7/10	6871 days	1%
Ann	7/10	6872 days	1%
ranker_584	9/10	6875 days	1%
Christine	7/10	6875 days	1%
Nina	9/10	6875 days	1%
Anthony	7/10	6880 days	1%
Tom Clements	7/10	6880 days	1%
ranker_46	8/10	6992 days	1%
Pat Brewster	8/10	6992 days	1%
FrankOosterwijk	6/10	7077 days	1%
Kim	8/10	7077 days	1%
Helen	7/10	7108 days	1%
Heather	9/10	7108 days	1%
Helene	9/10	7120 days	1%
John	7/10	7120 days	1%
Giancarlo	6/10	7120 days	1%
Annette	4/10	7144 days	0%
John	5/10	7144 days	0%
Duncan	9/10	7149 days	1%
Jen	4/10	7160 days	0%
Rolf	8/10	7168 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

-3.07% Adjustment

There may be an adjustment if this experience hasn't received any reviews within the last 68 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 190 days. Adjustments are according to the following table.

Days	Adjustment
…	…
187	-3.02%
188	-3.04%
189	-3.05%
190	-3.07%
191	-3.08%
192	-3.10%
193	-3.12%
…	…

Balancing Adjustment

9.54% 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.