• 
• 37%
• Created over 26 days

We counted 610 reviews for this product over the span of 2,463 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 26 days exceeding this threshold:

• 19 Reviews on May 27, 2017 (Avg. rating: 5.0)
• 17 Reviews on Aug 10, 2017 (Avg. rating: 4.7)
• 14 Reviews on Aug 28, 2017 (Avg. rating: 4.9)
• 14 Reviews on Jul 19, 2017 (Avg. rating: 4.7)
• 14 Reviews on Aug 29, 2017 (Avg. rating: 4.7)
• 13 Reviews on May 18, 2017 (Avg. rating: 4.9)
• 13 Reviews on Aug 22, 2017 (Avg. rating: 4.8)
• 12 Reviews on Aug 13, 2017 (Avg. rating: 4.7)
• 12 Reviews on Aug 9, 2017 (Avg. rating: 4.5)
• 10 Reviews on Aug 23, 2017 (Avg. rating: 5.0)
• 9 Reviews on Aug 25, 2017 (Avg. rating: 5.0)
• 9 Reviews on Aug 31, 2017 (Avg. rating: 4.6)
• 7 Reviews on Jun 14, 2017 (Avg. rating: 5.0)
• 7 Reviews on Aug 24, 2017 (Avg. rating: 4.9)
• 6 Reviews on Jan 13, 2015 (Avg. rating: 4.8)
• 6 Reviews on Jul 13, 2017 (Avg. rating: 4.3)
• 5 Reviews on Dec 21, 2014 (Avg. rating: 5.0)
• 5 Reviews on Jul 18, 2017 (Avg. rating: 4.4)
• 5 Reviews on Jul 28, 2017 (Avg. rating: 4.4)
• 4 Reviews on May 17, 2015 (Avg. rating: 5.0)
• 4 Reviews on Jul 14, 2017 (Avg. rating: 5.0)
• 4 Reviews on Jul 26, 2017 (Avg. rating: 5.0)
• 4 Reviews on Jan 12, 2015 (Avg. rating: 4.8)
• 4 Reviews on Apr 22, 2015 (Avg. rating: 4.8)
• 4 Reviews on Apr 23, 2015 (Avg. rating: 4.5)
• 4 Reviews on Jan 5, 2015 (Avg. rating: 4.0)
Show All

In total, we found that 225 reviews were created on just 26 days. The reviews on these high volume days have rated this product an average of 4.8 while reviews from other days have rated this product an average of 4.5. 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 Rating Trend test.

• 
• 40%
• Unverified Purchases

246 of the 610 total reviews for this product are unverified purchases. The unverified purchasers have rated this product an average of 4.8 while the verified purchasers have rated this product an average of 4.4. 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.

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.

One-Hit Wonders

• 
• 28%
• have only posted one review

172 of the 610 reviewers have only reviewed this product. The One-Hit Wonders have rated this product an average of 4.9 while the reviewers who have posted more than one review have rated this product an average of 4.5. 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.

Never-Verified Reviewers

• 
• 28%
• have zero verified purchases

170 of the 610 reviewers have never written a verified purchase review. The Never-Verified Reviewers have rated this product an average of 4.9 while the reviewers who have written at least one verified purchase review rated this product an average of 4.5. 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.

Take-Back Reviewers

• 
• 15%
• have previously deleted reviews

93 of the 610 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.

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 4.5, while the average ease score for reviewers in this category is 4.3. 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.

• 
• 55%
• From reviewers with an overrepresented participation

We see the following 1 participation group with a statistically significant greater concentration than what we'd expect to see:

• Reviewers with 1-5 Reviews: 54.6% (Avg. rating: 4.7)

In total, we found that 333 reviewers (or 55%) are within an overrepresented participation group. These reviews have rated this product an average of 4.7, while all other reviews have rated this product an average of 4.5. 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 Reviewer Participation test.

• 18
• Reviews have been deleted

We discovered a total of 18 deleted Reviews for this product, with an average rating of 4.5. 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

• 
• 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.

• 
• 4%
• Used substantial repetitive phrases

23 of the 610 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.

• 
• 6%
• Substantial overlapping review history

39 of the 610 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.

Brand Repeaters

• 
• 7%
• Reviewed other products from this brand

44 of the 610 reviewers have reviewed other products for this brand. 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 Brand Repeats test.

On Oct 3, 2016, Amazon prohibited incentivized reviews, however we still test for them since there are still millions in our dataset.

• 
• 3%
• Admitted to receiving an incentive

18 of the 610 total reviews for this product admitted to receiving a free or discounted product in exchange for a 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 Incentivized Reviews test. Check out our study showing that Incentivized Reviewers are much more likely to leave a positive review.