Interislander Ferry

Ranking Score Explained

Kia ora, 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

349 Valid Reviews

The Interislander Ferry experience has a total of 360 reviews. There are 349 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 349 valid reviews:

Rating	Count
10/10	40	11%
9/10	81	23%
8/10	103	30%
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	4	1%

77.13% Average

The raw data average (mean) for all the Interislander Ferry valid reviews is 77.13% and is based on 349 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 349 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

73.54%

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
Rina	9/10	98 days	100%
edm	1/10	372 days	38%
Colin Barrow	9/10	433 days	90%
Pauline	6/10	586 days	70%
Megan	5/10	738 days	53%
Marjolaine Loitz	4/10	768 days	44%
Keli Knox	10/10	1103 days	35%
Yar	1/10	1317 days	8%
Pinocity	6/10	1682 days	5%
Helen Russell	10/10	1863 days	5%
NewZealander	10/10	2137 days	4%
Tommy Pickett	9/10	2960 days	3%
Tom Bennett	8/10	2964 days	3%
Jeny Smolders	9/10	2966 days	3%
Gregg Wagstaff	7/10	3191 days	2%
Lianne Ijlst	8/10	3219 days	2%
Samantha and Neis	8/10	3220 days	2%
Brandon Cassidy	7/10	3236 days	2%
Vic Baughen	9/10	3238 days	2%
Anders Frank	7/10	3242 days	2%
Dina Schurer	8/10	3243 days	2%
Kim Youngsub	9/10	3244 days	2%
DEBBIE LAMBERT	10/10	3248 days	2%
Gary Williams	8/10	3248 days	2%
Kimberley Gardien	8/10	3255 days	2%
Antoine	9/10	3276 days	2%
Judit Van lanen	9/10	3281 days	2%
Bjorn Nielsen	8/10	3283 days	2%
Joel Virtanen	9/10	3285 days	2%
Corbin Hure	7/10	3285 days	2%
Ron	6/10	3288 days	2%
Thomas Simeon	8/10	3288 days	2%
Suzannah Hill	8/10	3289 days	2%
Kallan Mrozek	9/10	3290 days	2%
Kees Mol	9/10	3294 days	2%
Kristal Lavender	10/10	3294 days	2%
Bastian Bley	9/10	3295 days	2%
Jasmine Rogers	3/10	3296 days	1%
Louis Nilsson	8/10	3300 days	2%
Tim	7/10	3300 days	2%
Jendrik	6/10	3300 days	2%
Katharina	7/10	3301 days	2%
Chris Valchero	9/10	3304 days	2%
Rulp Niet	8/10	3306 days	2%
Soeren Buchheister	9/10	3307 days	2%
Chas Bronson	8/10	3307 days	2%
Jakob Lovdahl	9/10	3309 days	2%
Alexandra Schmidt	10/10	3319 days	2%
Jade Williams	10/10	3320 days	2%
Sam Staines	10/10	3321 days	2%
Nickolas Jonkergouw	7/10	3325 days	2%
Kirsty Smith	10/10	3325 days	2%
Eva Hesse	10/10	3340 days	2%
celine gries	8/10	3340 days	2%
tinagermany111	8/10	3355 days	2%
Cassandra Geyer	8/10	3539 days	2%
Olivier Reculeau	8/10	3540 days	2%
Thomas Michel	5/10	3541 days	1%
Lisa Haedrich	5/10	3545 days	1%
Nadja Guiliani	8/10	3549 days	2%
Elbrich	8/10	3549 days	2%
Jamie Serieux	7/10	3552 days	2%
Adele Jacques	9/10	3553 days	2%
Daniel Weber	6/10	3555 days	1%
Emily Noyd	8/10	3557 days	2%
Aparna Gula	10/10	3558 days	2%
Sebastiaan	7/10	3560 days	2%
Andre	9/10	3561 days	2%
Benedikt Hang	7/10	3562 days	1%
Yannick	8/10	3562 days	2%
S Black	9/10	3563 days	2%
Paul Larauze	6/10	3566 days	1%
Florence	6/10	3567 days	1%
Sarah Kovacs	8/10	3568 days	2%
Frenziska Schmid	7/10	3570 days	1%
Maud Livolsi	7/10	3577 days	1%
Lewis Whittle	6/10	3579 days	1%
Lukas Seager	6/10	3579 days	1%
Andrea Tabaka	8/10	3586 days	2%
Tina Rust	8/10	3588 days	2%
Joel Papak	8/10	3590 days	2%
Clemence and Pedro	9/10	3591 days	2%
Doms Wahlelr	9/10	3593 days	2%
Josef Biller	8/10	3593 days	2%
Justine Hoffmann	8/10	3594 days	2%
Friederike East	7/10	3594 days	1%
Mark White	10/10	3595 days	2%
Briony	8/10	3598 days	2%
Gabriel Siibers	8/10	3598 days	2%
Henry Wichler	8/10	3599 days	2%
Kyle Johnson	9/10	3601 days	2%
Niels Wezenberg	7/10	3602 days	1%
John Hamilton	9/10	3602 days	2%
Brianna Burd	9/10	3602 days	2%
Jessica Ruhland	8/10	3603 days	1%
Stula Vladimir	10/10	3604 days	2%
Cosmo Hartuna	7/10	3606 days	1%
Roland Fischer	6/10	3606 days	1%
Ross Holmes	9/10	3607 days	2%
Tilman	9/10	3609 days	2%
Petru	7/10	3610 days	1%
Fero Saarinen	6/10	3611 days	1%
Lauren Thompson	8/10	3613 days	1%
Meilin	8/10	3616 days	1%
Jonas Hoerning	10/10	3620 days	1%
Vanesha Patel	6/10	3621 days	1%
Mauricio Daniele	9/10	3621 days	1%
Sara and Antoine	8/10	3623 days	1%
Clare Pickford	6/10	3623 days	1%
Daniel Hill	10/10	3624 days	1%
Moritz Braun	7/10	3640 days	1%
Grischa Rodust	8/10	3647 days	1%
Chalie Dotesek	9/10	3648 days	1%
Julien Lafeville	7/10	3652 days	1%
Julia Huesam	8/10	3652 days	1%
Alexandre	9/10	3656 days	1%
Kev Zarka	6/10	3657 days	1%
Markus Wabing	8/10	3660 days	1%
Gessica	6/10	3693 days	1%
Simon Quass	9/10	3697 days	1%
Barthelemy	7/10	3926 days	1%
Brita Topp	10/10	4269 days	0%
Laim Thompson	8/10	4269 days	0%
Adriana	10/10	4277 days	0%
Pavel Jarolimek	5/10	4277 days	0%
Leonie Moeller	6/10	4278 days	0%
Doreen Gendel	8/10	4279 days	0%
Carla Oyarzun	3/10	4282 days	0%
Paolo Cases	3/10	4282 days	0%
Wolfgang and Christine	8/10	4287 days	0%
Helen	8/10	4300 days	0%
Olivier Carval	9/10	4302 days	0%
Hirsch Svenja	9/10	4303 days	0%
Mahr Svenja	8/10	4303 days	0%
Anna Guzewiez	9/10	4319 days	0%
Pier Durand	8/10	4323 days	0%
Serena Poggioli	9/10	4323 days	0%
Wayne Schist	7/10	4323 days	0%
Margreth Lydie	5/10	4331 days	0%
Laura Pleumeekers	7/10	4345 days	0%
David Brooks	10/10	4348 days	0%
Adrien Godeloup	9/10	4357 days	0%
Bet Dreno	8/10	4358 days	0%
Joachim	1/10	4359 days	0%
Pioter Jurkowski	7/10	4359 days	0%
Thomas Roche	9/10	4361 days	0%
Brian	9/10	4420 days	1%
hendrik king	9/10	4543 days	1%
Kiki Wykstra	5/10	4653 days	1%
Galen Licht	4/10	4653 days	1%
Yu-Ti Chu	7/10	4656 days	1%
Ton Martens	7/10	4656 days	1%
Joshua Perry	8/10	4661 days	1%
Molly Ladd	8/10	4661 days	1%
Michael Nolan	9/10	4665 days	1%
Julian Roots	9/10	4665 days	1%
Florent Corino	9/10	4669 days	1%
Amiot Cyriane	7/10	4669 days	1%
Annika	7/10	4669 days	1%
Jonas Herrmann	7/10	4669 days	1%
Matthieu Daveou	8/10	4669 days	1%
Julien Panossian	6/10	4669 days	1%
Raoul Montestruer	5/10	4669 days	1%
Alessa Ndra	8/10	4675 days	1%
Bjorn Hedmark	5/10	4676 days	1%
Evyatar Tulipman	7/10	4678 days	1%
S Curry	10/10	4693 days	1%
Ingrid	9/10	4737 days	1%
Reinier Timmer	7/10	4737 days	1%
Moorman	8/10	4746 days	1%
Stefan Roth	9/10	4771 days	1%
David	9/10	4785 days	1%
kevindang	10/10	4938 days	1%
Ruben Kunze	4/10	5020 days	1%
Sebastian Hol	9/10	5026 days	1%
Dick Stewart	8/10	5035 days	1%
David Beaumont	9/10	5042 days	1%
Beyeler	10/10	5047 days	1%
Nikita Sue	9/10	5052 days	1%
Schweiger	10/10	5054 days	1%
Jan & Marian	10/10	5133 days	1%
Konny	9/10	5137 days	1%
Waldemar Schuler	8/10	5137 days	1%
jule	3/10	5151 days	1%
Jack Potman	8/10	5353 days	1%
Jon_and_Family	9/10	5365 days	1%
Walker	9/10	5368 days	1%
Andreas Blessing	10/10	5376 days	1%
Gema	7/10	5379 days	1%
Avry Fabrice	6/10	5384 days	1%
Diane Johnston	9/10	5389 days	1%
Javier Munoz	8/10	5389 days	1%
Ben Akin-Smith	8/10	5390 days	1%
K Wallis	9/10	5395 days	1%
khs	9/10	5396 days	1%
Emma Ducat	9/10	5396 days	1%
Mr and Mrs Lambert	8/10	5403 days	1%
Andrew Koster	7/10	5409 days	1%
Bakker	8/10	5409 days	1%
Kimberly St Louis	8/10	5410 days	1%
Roel Wesstra	8/10	5416 days	1%
Seifert	10/10	5416 days	1%
Derek Woodward	9/10	5418 days	1%
Fabi & Sabi	8/10	5419 days	1%
Rosey834	8/10	5486 days	1%
Pete & Chris	10/10	5686 days	1%
Tony Masters	9/10	5749 days	1%
Hershell	8/10	5753 days	1%
Mike Robinson	9/10	5754 days	1%
Brent S	2/10	5755 days	0%
Zara Leyden	9/10	5763 days	1%
Judith	7/10	5767 days	1%
anon	8/10	5768 days	1%
Pierre Pilon	8/10	5769 days	1%
Jenny Omb	1/10	5774 days	0%
Frei Urs	6/10	5775 days	1%
Bryan Keddie	9/10	5785 days	1%
Leanne Rogan	5/10	5785 days	1%
Joanne Clarke	8/10	5789 days	1%
Wolfgang G	9/10	5795 days	1%
Thomas Signes	7/10	5816 days	1%
menzel	10/10	5834 days	1%
graemeh1	9/10	5835 days	1%
klinger	10/10	5835 days	1%
gereldineb	8/10	5845 days	1%
jennyb	9/10	5849 days	1%
Frank de Voogd	8/10	5855 days	1%
Jean Paul Mesnage	9/10	5861 days	1%
Hansjoerg Ehrmann	5/10	5862 days	1%
Daniel Alonso	9/10	5863 days	1%
Nigel Petrie	9/10	5874 days	1%
Tracy & Peter Cassidy	8/10	5890 days	1%
miniappleses	8/10	5912 days	1%
Josie Boyle	7/10	6023 days	1%
JanneP	9/10	6093 days	1%
Mikey	9/10	6100 days	1%
SablotniD	7/10	6105 days	1%
WiebkeS	9/10	6111 days	1%
Tanya	5/10	6112 days	1%
Jan	6/10	6113 days	1%
Viola	8/10	6114 days	1%
RowanL	7/10	6115 days	1%
VickiEngland	8/10	6123 days	1%
TomC1	8/10	6128 days	1%
AndyK	9/10	6128 days	1%
TatiamT	9/10	6128 days	1%
GillianK	8/10	6130 days	1%
EelcoK	9/10	6130 days	1%
Michael	9/10	6134 days	1%
soccaplaya14	10/10	6135 days	1%
Eugene	7/10	6136 days	1%
John	6/10	6139 days	1%
Tony	8/10	6143 days	1%
Middleton	4/10	6144 days	1%
Elise	8/10	6146 days	1%
Marie	8/10	6146 days	1%
ThomasS1	10/10	6150 days	1%
RasmusB	4/10	6152 days	1%
Simon	8/10	6157 days	1%
Phil&Joe	10/10	6160 days	1%
Marcus	7/10	6160 days	1%
Andre	7/10	6161 days	1%
Iris	9/10	6163 days	1%
Carla	7/10	6163 days	1%
Sandra	8/10	6167 days	1%
Schaffluber	10/10	6168 days	1%
Hayley	5/10	6169 days	1%
Con	2/10	6213 days	0%
felix	7/10	6214 days	1%
melissa	10/10	6221 days	1%
John B	5/10	6223 days	1%
Gemma	7/10	6262 days	1%
Henry	7/10	6262 days	1%
Antonella	10/10	6270 days	1%
Michelle	8/10	6270 days	1%
Laura	7/10	6279 days	1%
Sarah	8/10	6293 days	1%
Katerina	7/10	6314 days	1%
Erin	3/10	6314 days	1%
Mike Knight	9/10	6335 days	1%
Bronagh Mcartan	8/10	6343 days	1%
Dave	8/10	6354 days	1%
fgregory	10/10	6358 days	1%
Rhea	6/10	6403 days	1%
Georgina Mulligan	8/10	6415 days	1%
Karen C	7/10	6427 days	1%
Edmund Hillstone	10/10	6444 days	1%
Toby	6/10	6467 days	1%
Jennifer Baulch	9/10	6471 days	1%
Susan	8/10	6475 days	1%
Hoetnagels	7/10	6478 days	1%
Alan Bellerby	8/10	6481 days	1%
Sanne Jonker	7/10	6482 days	1%
Renske Tehurne	8/10	6486 days	1%
Benjamin Krein	7/10	6486 days	1%
Anne and Derek	8/10	6487 days	1%
James Davies	7/10	6487 days	1%
Naomi Horton	8/10	6488 days	1%
Roger Repolusk	8/10	6492 days	1%
Tony Wicks	6/10	6492 days	1%
Nancy Dol	8/10	6492 days	1%
Kristine	10/10	6492 days	1%
Kathy Hawey	9/10	6494 days	1%
David Buckley	8/10	6495 days	1%
Lena1	6/10	6495 days	1%
John Woodrow	8/10	6496 days	1%
Carmen Dolny	10/10	6496 days	1%
Haemnerli	8/10	6500 days	1%
Carla	8/10	6507 days	1%
Jim Curley	8/10	6507 days	1%
paulonline	7/10	6513 days	1%
Bex	6/10	6522 days	1%
Jenny Hulsebosch	8/10	6523 days	1%
Melissa Steedman	8/10	6534 days	1%
Tim	7/10	6535 days	1%
Falk Seidel	7/10	6538 days	1%
Hans Olthof	8/10	6538 days	1%
Anu	9/10	6541 days	1%
Anneli	6/10	6543 days	1%
purplekat99	10/10	6551 days	1%
Connor	10/10	6564 days	1%
Ad	7/10	6564 days	1%
Ann Westmacott	5/10	6569 days	1%
Paul Cowie	8/10	6570 days	1%
Ewen Maclean	8/10	6570 days	1%
Sarah Wilton	5/10	6570 days	1%
Arend v Dyn	7/10	6572 days	1%
Linda	8/10	6576 days	1%
Fiona	7/10	6576 days	1%
Ann	7/10	6577 days	1%
ranker_584	9/10	6580 days	1%
Christine	7/10	6580 days	1%
Nina	9/10	6580 days	1%
Anthony	7/10	6585 days	1%
Tom Clements	7/10	6585 days	1%
ranker_46	8/10	6697 days	1%
Pat Brewster	8/10	6697 days	1%
FrankOosterwijk	6/10	6782 days	1%
Kim	8/10	6782 days	1%
Helen	7/10	6813 days	1%
Heather	9/10	6813 days	1%
Helene	9/10	6825 days	1%
John	7/10	6825 days	1%
Giancarlo	6/10	6825 days	1%
Annette	4/10	6849 days	1%
John	5/10	6849 days	1%
Duncan	9/10	6854 days	1%
Jen	4/10	6865 days	1%
Rolf	8/10	6873 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

-1.81% Adjustment

There may be an adjustment if this experience hasn't received any reviews within the last 42 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 89 days. Adjustments are according to the following table.

Days	Adjustment
…	…
86	-1.75%
87	-1.77%
88	-1.79%
89	-1.81%
90	-1.83%
91	-1.85%
92	-1.87%
…	…

Balancing Adjustment

6.08% 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

78%

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.