Ranking Score Explained

Hi there, 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 Milford Discovery Centre & Underwater Observatory.

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.

Nick Morrison's avatar

Nick Morrison

Rankers owner

Milford Discovery Centre & Underwater Observatory

Valid Reviews

15 Valid Reviews

The Milford Discovery Centre & Underwater Observatory experience has a total of 15 valid reviews. There are no 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 15 valid reviews:

Rating Count Percentage
10/10 2
13%
9/10 2
13%
8/10 4
27%
7/10 2
13%
6/10 2
13%
5/10 0
0%
4/10 0
0%
3/10 1
7%
2/10 1
7%
1/10 1
7%

68.00% Average

The raw data average (mean) for all the Milford Discovery Centre & Underwater Observatory valid reviews is 68.00% and is based on 15 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

12 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 15 valid reviews, the experience has 12 face-to-face reviews collected during interviews by our team.

Below is the distribution of ratings for the 12 face-to-face reviews:

Rating Count Percentage
10/10 1
8%
9/10 2
17%
8/10 4
33%
7/10 2
17%
6/10 1
8%
5/10 0
0%
4/10 0
0%
3/10 1
8%
2/10 1
8%
1/10 0
0%

70.83% Average

The raw data average (mean) for all the Milford Discovery Centre & Underwater Observatory face-to-face reviews is 70.83% and is based on 12 face-to-face reviews. This value is not used to calculate the ranking score and it only provided here for comparison purposes.

Weighted Average

79.86%

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 Face-to-Face Weight Relative Weight
David 10/10 1365 days true 4.47 100%
Regina Baum 8/10 1701 days true 3.62 81%
Carmen 8/10 2053 days true 2.97 66%
Niamh Duane 7/10 2411 days true 2.21 49%
Claudia 6/10 2490 days true 1.88 42%
Sharlene 1/10 3310 days 0.49 11%
Maite Severins 9/10 3543 days true 0.21 5%
VisualDelight 10/10 3736 days 0.0 0%
amyd 6/10 4254 days 0.0 0%
Katerina 9/10 4441 days true 0.0 0%
Rob Poels 8/10 4600 days true 0.0 0%
Klaus Uhl 3/10 4606 days true 0.0 0%
John Howlett 8/10 4639 days true 0.0 0%
Charlie Wilson 2/10 4790 days true 0.0 0%
Ralph 7/10 4988 days true 0.0 0%

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 Milford Discovery Centre & Underwater Observatory experience has plenty of reviews and does not meet the criteria for any adjustment.

Recent Reviews Adjustment

-3.73% Adjustment

There may be an adjustment if this experience hasn't received any reviews within the last 54 days. However the Milford Discovery Centre & Underwater Observatory 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 Milford Discovery Centre & Underwater Observatory experience has been adjusted for 200 days. Adjustments are according to the following table.

Days Adjustment
197 -3.67%
198 -3.69%
199 -3.71%
200 -3.73%
201 -3.75%
202 -3.77%
203 -3.78%

Final Ranking Score

76%

The final ranking score once adjustments and rounding has been applied. This value is cached and recalculated each day. Therefore it may not be precisely accurate based on the other values presented.

If you have any questions or comments about our ranking score calculation please get in touch at info@rankers.co.nz.