Never-Verified Reviewers

• 
• 35%
• have zero verified purchases

18 of the 51 reviewers have never written a verified purchase review. While this is more Never-Verified Reviewers than we'd expect to see, the discrepancy in ratings between the Never-Verified Reviewers and reviewers who have written at least one verified purchase review isn't significant enough to rule out the possibility of it being due to random chance.

Take-Back Reviewers

• 
• 53%
• have previously deleted reviews

27 of the 51 reviewers have had at least one of their past reviews for another product deleted. This is an excessively large percentage of Take-Back Reviewers which may indicate unnatural reviews.

Read more about our Suspicious Reviewers test.

• 
• 27%
• Created over 2 days

We counted 51 reviews for this product over the span of 458 days, an average of 0.1 reviews per day. If these reviews were created randomly, there would be a 99.9% chance that we would see 2 or fewer reviews on any given day.

However, we see the following 2 days exceeding this threshold:

• 11 Reviews on Oct 8, 2015 (Avg. rating: 9.7)
• 3 Reviews on Oct 11, 2015 (Avg. rating: 9.3)

In total, we found that 14 reviews were created on just 2 days. This is an excessively high number of reviews submitted on these high volume days.

Read more about our Rating Trend test.

• 
• 98%
• Unverified Purchases

50 of the 51 total reviews for this product are unverified purchases. This is an excessively large percentage of unverified purchases and it may indicate unnatural reviews.

Unverified purchases may be the result of Kindle Unlimited readers, buyers who didn't pay full price, or reviewers who did not purchase the product at Amazon. Read more about our Unverified Purchases test.

Brand Repeaters

• 
• 33%
• Reviewed other products from this brand

17 of the 51 reviewers have reviewed other products for this brand. While this is more Brand Repeaters than we'd expect to see, the discrepancy in ratings between the Brand Repeaters and non-repeaters isn't significant enough to rule out the possibility of it being due to random chance.

Read more about our Brand Repeats test.

The ease score is the average rating for all reviews that a given reviewer submits. The average ease score for reviewers of this product is 9.1, while the average ease score for reviewers in this category is 8.8. While this discrepancy is rather large, it is not quite large enough to rule out the possibility of it being due random chance.

• 
• 31%
• Have an overrepresented word count

In the graph above, we can see the distribution of review word counts for this product and the expected distribution for this category. We see the following 1 group with a statistically significant greater concentration than what we'd expect to see:

• 66-100 words: 31.4% (Avg. rating: 9.3)

In total, we found that 16 reviews (or 31%) are within an overrepresented word count group. While this is more reviews from overrepresented word count groups than we'd expect to see, these reviews do not appear to have a significant impact on the overall rating.

Read more about our Word Count Comparison test.

• 
• 45%
• Used substantial repetitive phrases

23 of the 51 total reviews for this product use substantial repetitive phrases between them. This is an excessively large percentage which may indicate unnatural reviews.

Read more about our Phrase Repetition test.

• 
• 75%
• Substantial overlapping review history

38 of the 51 reviewers have substantial overlapping product review history. While this is more than we'd expect to see, it does not appear to have a significant impact on the overall rating.

Read more about our Overlapping Review History test.

• 
• 41%
• From reviewers with an overrepresented participation

We see the following 2 participation groups with a statistically significant greater concentration than what we'd expect to see:

• Reviewers with 31-50 Reviews: 25.5% (Avg. rating: 9.3)
• Reviewers with 51-100 Reviews: 15.7% (Avg. rating: 9.0)

In total, we found that 21 reviewers (or 41%) are within an overrepresented participation group. While this is more reviews from overrepresented participation groups than we'd expect to see, these reviews do not appear to have a significant impact on the overall rating.

Read more about our Reviewer Participation test.

• 
• 4%
• Mentioned the word "Sample"

2 of the 51 total reviews for this product mentioned the word "sample" within their review. This is within an acceptable range and it does not appear to be significantly affecting the overall rating for this product.

Read more about our Sample Reviews test.

• 0
• Reviews have been deleted

We have not discovered any deleted reviews for this product.

There are a few limitations to keep in mind regarding the Deleted Reviews test:

1. We don't have a magic ability to collect every single deleted review; we can only identify reviews as deleted if we collect them on one date and then notice they are no longer visible on a subsequent date.
2. We have no information on reviews that were never published in the first place.
3. We also don't know why these reviews were removed. It could be action from the platform, personal decision by the review author, part of an entire account closure, even some data error on our part, etc.

Read more about our Deleted Reviews test.