• 
• 3%
• Created over 3 days

We counted 349 reviews for this product over the span of 1,993 days, an average of 0.2 reviews per day. If these reviews were created randomly, there would be a 99.9% chance that we would see 3 or fewer reviews on any given day.

However, we see the following 3 days exceeding this threshold:

• 4 Reviews on Jul 31, 2013 (Avg. rating: 9.8)
• 4 Reviews on Aug 1, 2013 (Avg. rating: 9.0)
• 4 Reviews on Mar 1, 2012 (Avg. rating: 8.8)

In total, we found that 12 reviews were created on just 3 days. The reviews on these high volume days have rated this product an average of 9.2 while reviews from other days have rated this product an average of 7.7. 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.

Read more about our Rating Trend test.

Brand Loyalists

• 
• 7%
• Reviewed mostly products from this brand

26 of the 349 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.

Read more about our Brand Repeats test.

One-Hit Wonders

• 
• 32%
• have only posted one review

110 of the 349 reviewers have only reviewed this product. This is an excessively large percentage of One-Hit Wonders which may indicate unnatural reviews.

Take-Back Reviewers

• 
• 17%
• have previously deleted reviews

61 of the 349 reviewers have had at least one of their past reviews for another product deleted. The Take-Back Reviewers have rated this product an average of 8.3 while the reviewers who don't have any deleted reviews in their history have rated this product an average of 7.7. 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.

Single-Day Reviewers

• 
• 15%
• have posted all their reviews on a single day

53 of the 349 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, the discrepancy in ratings between the Single-Day Reviewers and all other reviewers isn't significant enough to rule out the possibility of it being due to random chance.

Read more about our Suspicious Reviewers test.

• 8
• Reviews have been deleted

We discovered a total of 8 deleted Reviews for this product, with an average rating of 6.9. Even though deleted reviews don't affect the average rating, the fact that action was taken to delete reviews raises some red flags about the integrity of the reviews for the product as whole.

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.

Show distribution of deleted reviews

• 
• 27%
• Unverified Purchases

94 of the 349 total reviews for this product are unverified purchases. This is within an acceptable range and it does not appear to be significantly affecting the overall rating for this product.

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.

• 
• 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

11 of the 349 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.

• 
• 38%
• Substantial overlapping review history

131 of the 349 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 8.1, while the average ease score for reviewers in this category is 8.8.

• 
• 1%
• Mentioned the word "Sample"

2 of the 349 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.