• 15
• Reviews have been deleted

We discovered a total of 15 deleted Reviews for this product, with an average rating of 9.9. 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

• 
• 53%
• Created over 10 days

We counted 210 reviews for this product over the span of 537 days, an average of 0.4 reviews per day. If these reviews were created randomly, there would be a 99.9% chance that we would see 4 or fewer reviews on any given day.

However, we see the following 10 days exceeding this threshold:

• 19 Reviews on Feb 2, 2016 (Avg. rating: 9.8)
• 17 Reviews on Jan 31, 2016 (Avg. rating: 10.0)
• 14 Reviews on Feb 1, 2016 (Avg. rating: 9.9)
• 14 Reviews on Jan 27, 2016 (Avg. rating: 9.5)
• 12 Reviews on Feb 9, 2016 (Avg. rating: 10.0)
• 12 Reviews on Mar 22, 2016 (Avg. rating: 9.6)
• 7 Reviews on Feb 4, 2016 (Avg. rating: 9.7)
• 6 Reviews on Feb 29, 2016 (Avg. rating: 9.7)
• 6 Reviews on Jan 28, 2016 (Avg. rating: 8.8)
• 5 Reviews on Feb 5, 2016 (Avg. rating: 9.8)
Show All

In total, we found that 112 reviews were created on just 10 days. The reviews on these high volume days have rated this product an average of 9.7 while reviews from other days have rated this product an average of 9.4. 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 Repeaters

• 
• 71%
• Reviewed other products from this brand

149 of the 210 reviewers have reviewed other products for this brand. This is an excessively large percentage of Brand Repeaters which may indicate unnatural reviews.

Brand Loyalists

• 
• 60%
• Reviewed mostly products from this brand

125 of the 210 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

• 
• 30%
• Reviewed only products from this brand

63 of the 210 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

• 
• 19%
• have only posted one review

39 of the 210 reviewers have only reviewed this product. While this is more One-Hit Wonders than we'd expect to see, it does not appear to have a significant impact on the overall rating.

Never-Verified Reviewers

• 
• 68%
• have zero verified purchases

142 of the 210 reviewers have never written a verified purchase review. This is an excessively large percentage of Never-Verified Reviewers which may indicate unnatural reviews.

Take-Back Reviewers

• 
• 11%
• have previously deleted reviews

23 of the 210 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.

Single-Day Reviewers

• 
• 32%
• have posted all their reviews on a single day

68 of the 210 reviewers have written multiple reviews but posted all of them on a single day. The Single-Day reviewers have rated this product an average of 9.8 while all other reviewers rated this product an average of 9.5. 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 Suspicious Reviewers 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 9.5, while the average ease score for reviewers in this category is 8.8. 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.

• 
• 80%
• Unverified Purchases

169 of the 210 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.

• 
• 20%
• 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:

• 6-15 words: 19.5% (Avg. rating: 9.7)

In total, we found that 41 reviews (or 20%) are within an overrepresented word count group. 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 Word Count Comparison test.

• 
• 8%
• Used substantial repetitive phrases

16 of the 210 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.

• 
• 26%
• Substantial overlapping review history

55 of the 210 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.

• 
• 4%
• Mentioned the word "Sample"

8 of the 210 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.