• 
• 27%
• Created over 23 days

We counted 774 reviews for this product over the span of 913 days, an average of 0.8 reviews per day. If these reviews were created randomly, there would be a 99.9% chance that we would see 5 or fewer reviews on any given day.

However, we see the following 23 days exceeding this threshold:

• 21 Reviews on Nov 3, 2017 (Avg. rating: 5.0)
• 19 Reviews on Dec 17, 2017 (Avg. rating: 4.8)
• 12 Reviews on Nov 4, 2017 (Avg. rating: 4.9)
• 11 Reviews on Nov 6, 2017 (Avg. rating: 4.8)
• 10 Reviews on Jan 11, 2018 (Avg. rating: 4.9)
• 10 Reviews on Nov 14, 2017 (Avg. rating: 4.7)
• 10 Reviews on Jan 10, 2018 (Avg. rating: 4.7)
• 10 Reviews on Nov 10, 2017 (Avg. rating: 4.4)
• 9 Reviews on Oct 29, 2017 (Avg. rating: 4.9)
• 8 Reviews on Jan 30, 2018 (Avg. rating: 4.8)
• 7 Reviews on Dec 18, 2017 (Avg. rating: 5.0)
• 7 Reviews on Oct 30, 2017 (Avg. rating: 4.9)
• 7 Reviews on Nov 5, 2017 (Avg. rating: 4.9)
• 7 Reviews on Dec 8, 2017 (Avg. rating: 4.9)
• 7 Reviews on Jan 25, 2018 (Avg. rating: 4.7)
• 7 Reviews on Oct 28, 2017 (Avg. rating: 4.6)
• 7 Reviews on Dec 2, 2017 (Avg. rating: 4.6)
• 7 Reviews on Jan 9, 2018 (Avg. rating: 4.3)
• 6 Reviews on Oct 27, 2017 (Avg. rating: 5.0)
• 6 Reviews on Feb 20, 2018 (Avg. rating: 5.0)
• 6 Reviews on Nov 15, 2017 (Avg. rating: 4.8)
• 6 Reviews on Dec 13, 2017 (Avg. rating: 4.3)
• 6 Reviews on Nov 24, 2017 (Avg. rating: 4.0)
Show All

In total, we found that 206 reviews were created on just 23 days. This is an excessively high number of reviews submitted on these high volume days.

Read more about our Rating Trend 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. While this discrepancy is rather large, it is not quite large enough to rule out the possibility of it being due random chance.

• 
• 38%
• 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 6-15 Reviews: 38.1% (Avg. rating: 4.7)

In total, we found that 295 reviewers (or 38%) 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.

• 
• 17%
• Unverified Purchases

133 of the 774 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.

• 
• 23%
• 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:

• 16-25 words: 23.0% (Avg. rating: 4.7)

In total, we found that 178 reviews (or 23%) 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.

• 
• 10%
• Used substantial repetitive phrases

81 of the 774 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.

One-Hit Wonders

• 
• 6%
• have only posted one review

45 of the 774 reviewers have only reviewed this product. This is within an acceptable range and it does not appear to be significantly affecting the overall rating for this product.

Never-Verified Reviewers

• 
• 4%
• have zero verified purchases

28 of the 774 reviewers have never written a verified purchase review. This is within an acceptable range and it does not appear to be significantly affecting the overall rating for this product.

Take-Back Reviewers

• 
• 21%
• have previously deleted reviews

162 of the 774 reviewers have had at least one of their past reviews for another product deleted. This is within an acceptable range and it does not appear to be significantly affecting the overall rating for this product.

Single-Day Reviewers

• 
• 1%
• have posted all their reviews on a single day

7 of the 774 reviewers have written multiple reviews but posted all of them on a single day. 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 Suspicious Reviewers test.

• 
• 16%
• Substantial overlapping review history

121 of the 774 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

We didn't detect a substantial amount of Brand Repeaters.

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

1 of the 774 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.

• 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.