• 
• 45%
• Unverified Purchases

13 of the 29 total reviews for this product are unverified purchases. The unverified purchasers have rated this product an average of 9.9 while the verified purchasers have rated this product an average of 8.6. Based on our statistical modeling, the discrepancy in average rating between these two groups is significant enough to believe that the difference is not due to random chance, and may indicate that there are 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 Loyalists

• 
• 14%
• Reviewed mostly products from this brand

4 of the 29 reviewers have reviewed multiple products but half or more of their reviews are for this brand. This is an excessively large percentage of Brand Loyalists which may indicate unnatural reviews.

Brand Monogamists

• 
• 7%
• Reviewed only products from this brand

2 of the 29 reviewers have reviewed multiple products, but only for this brand. This is an excessively large percentage of Brand Monogamists which may indicate unnatural reviews.

Read more about our Brand Repeats test.

One-Hit Wonders

• 
• 38%
• have only posted one review

11 of the 29 reviewers have only reviewed this product. This is an excessively large percentage of One-Hit Wonders which may indicate unnatural reviews.

Never-Verified Reviewers

• 
• 34%
• have zero verified purchases

10 of the 29 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

• 
• 3%
• have previously deleted reviews

1 of the 29 reviewers have had at least one of their past reviews for another product deleted. While this is more Take-Back Reviewers than we'd expect to see, the discrepancy in ratings between the Take-Back Reviewers and reviewers who don't have any deleted reviews in their history isn't significant enough to rule out the possibility of it being due to random chance.

Single-Day Reviewers

• 
• 21%
• have posted all their reviews on a single day

6 of the 29 reviewers have written multiple reviews but posted all of them on a single day. While this is more Single-Day Reviewers than we'd expect to see, it does not appear to have a significant impact on the overall rating.

Read more about our Suspicious Reviewers test.

• 
• 7%
• Created over 1 day

We counted 29 reviews for this product over the span of 2,629 days, an average of 0.0 reviews per day. If these reviews were created randomly, there would be a 99.9% chance that we would see 1 or fewer reviews on any given day.

However, we see the following 1 day exceeding this threshold:

• 2 Reviews on Oct 4, 2013 (Avg. rating: 9.0)

In total, we found that 2 reviews were created on just 1 day. Although any days with a larger number of reviews than expected is suspicious, these reviews do not appear to have a significant impact on the overall rating.

Read more about our Rating Trend test.

• 
• 0%
• Have an overrepresented word count

We didn't find any review word count groups that had a statistically significant greater concentration than what we'd expect to see in this category.
Read more about our Word Count Comparison test.

• 
• 3%
• Used substantial repetitive phrases

1 of the 29 total reviews for this product use substantial repetitive phrases between them. 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 Phrase Repetition test.

• 
• 34%
• Substantial overlapping review history

10 of the 29 reviewers have substantial overlapping product review history. 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 Overlapping Review History test.

• 
• 0%
• From reviewers with an overrepresented participation

We didn't find any participation groups that had a statistically significant greater concentration than what we'd expect to see in this category.
Read more about our Reviewer Participation 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 8.8, while the average ease score for reviewers in this category is 8.8.

• 
• 0%
• Mentioned the word "Sample"

We didn't find the word "sample" used in any reviews
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.