• 
• 26%
• Created over 30 days

We counted 396 reviews for this product over the span of 3,717 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 30 days exceeding this threshold:

• 5 Reviews on Feb 6, 2014 (Avg. rating: 5.0)
• 4 Reviews on Apr 16, 2013 (Avg. rating: 5.0)
• 4 Reviews on May 2, 2013 (Avg. rating: 5.0)
• 4 Reviews on May 16, 2013 (Avg. rating: 5.0)
• 4 Reviews on Feb 5, 2014 (Avg. rating: 5.0)
• 4 Reviews on Mar 25, 2015 (Avg. rating: 5.0)
• 4 Reviews on Jul 2, 2015 (Avg. rating: 5.0)
• 4 Reviews on Jan 18, 2017 (Avg. rating: 5.0)
• 4 Reviews on Aug 22, 2017 (Avg. rating: 5.0)
• 4 Reviews on Jul 15, 2016 (Avg. rating: 4.0)
• 4 Reviews on Jul 25, 2017 (Avg. rating: 4.0)
• 4 Reviews on Sep 14, 2016 (Avg. rating: 3.5)
• 3 Reviews on Jul 31, 2010 (Avg. rating: 5.0)
• 3 Reviews on Jul 8, 2013 (Avg. rating: 5.0)
• 3 Reviews on Jul 17, 2014 (Avg. rating: 5.0)
• 3 Reviews on Aug 20, 2014 (Avg. rating: 5.0)
• 3 Reviews on Jun 30, 2015 (Avg. rating: 5.0)
• 3 Reviews on Sep 25, 2015 (Avg. rating: 5.0)
• 3 Reviews on Oct 8, 2015 (Avg. rating: 5.0)
• 3 Reviews on Jan 22, 2016 (Avg. rating: 5.0)
• 3 Reviews on Feb 29, 2016 (Avg. rating: 5.0)
• 3 Reviews on Mar 29, 2016 (Avg. rating: 5.0)
• 3 Reviews on Apr 21, 2016 (Avg. rating: 5.0)
• 3 Reviews on Aug 7, 2016 (Avg. rating: 5.0)
• 3 Reviews on Sep 28, 2016 (Avg. rating: 5.0)
• 3 Reviews on Dec 30, 2016 (Avg. rating: 5.0)
• 3 Reviews on Sep 10, 2017 (Avg. rating: 5.0)
• 3 Reviews on Oct 19, 2014 (Avg. rating: 4.0)
• 3 Reviews on Aug 22, 2015 (Avg. rating: 4.0)
• 3 Reviews on May 13, 2019 (Avg. rating: 2.7)
Show All

In total, we found that 103 reviews were created on just 30 days. The reviews on these high volume days have rated this product an average of 4.7 while reviews from other days have rated this product an average of 4.2. 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.

One-Hit Wonders

• 
• 4%
• have only posted one review

15 of the 396 reviewers have only reviewed this product. The One-Hit Wonders have rated this product an average of 2.9 while the reviewers who have posted more than one review 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.

Never-Verified Reviewers

• 
• 1%
• have zero verified purchases

2 of the 396 reviewers have never written a verified purchase review. The Never-Verified Reviewers have rated this product an average of 1.0 while the reviewers who have written at least one verified purchase review 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.

Take-Back Reviewers

• 
• 44%
• have previously deleted reviews

175 of the 396 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 4.6 while the reviewers who don't have any deleted reviews in their history have rated this product an average of 4.2. 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.

• 
• 22%
• Used substantial repetitive phrases

87 of the 396 total reviews for this product use substantial repetitive phrases between them. These reviewers have rated this product an average of 4.8 while reviews without substantial repetitive phrases rated this product an average of 4.2. 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 Phrase Repetition test.

Brand Repeaters

• 
• 37%
• Reviewed other products from this brand

147 of the 396 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.

Brand Loyalists

• 
• 4%
• Reviewed mostly products from this brand

14 of the 396 reviewers have reviewed multiple products but half or more of their reviews are for this brand. While this is more Brand Loyalists than we'd expect to see, the discrepancy in ratings between the Brand Loyalists and non-loyalists isn't significant enough to rule out the possibility of it being due to random chance.

Read more about our Brand Repeats 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 1-5 Reviews: 18.7% (Avg. rating: 3.9)
• Reviewers with 6-15 Reviews: 22.7% (Avg. rating: 4.1)

In total, we found that 164 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%
• Unverified Purchases

17 of the 396 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.

• 
• 5%
• Substantial overlapping review history

20 of the 396 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.

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

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

• 
• 0%
• Admitted to receiving an incentive

We didn't detect any reviews that used language indicating they were incentivized.
Read more about our Incentivized Reviews test. Check out our study showing that Incentivized Reviewers are much more likely to leave a positive review.

• 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.