• 
• 53%
• Created over 28 days

We counted 737 reviews for this product over the span of 1,008 days, an average of 0.7 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 28 days exceeding this threshold:

• 41 Reviews on Sep 7, 2020 (Avg. rating: 4.9)
• 28 Reviews on Sep 8, 2020 (Avg. rating: 5.0)
• 27 Reviews on Sep 5, 2020 (Avg. rating: 4.9)
• 21 Reviews on Sep 9, 2020 (Avg. rating: 4.9)
• 19 Reviews on Sep 13, 2020 (Avg. rating: 4.9)
• 18 Reviews on Sep 12, 2020 (Avg. rating: 4.6)
• 17 Reviews on Sep 6, 2020 (Avg. rating: 5.0)
• 17 Reviews on Sep 14, 2020 (Avg. rating: 4.9)
• 17 Reviews on Sep 15, 2020 (Avg. rating: 4.9)
• 17 Reviews on Sep 16, 2020 (Avg. rating: 4.4)
• 14 Reviews on Sep 10, 2020 (Avg. rating: 4.9)
• 13 Reviews on Sep 11, 2020 (Avg. rating: 4.9)
• 12 Reviews on Sep 19, 2020 (Avg. rating: 4.9)
• 12 Reviews on Sep 20, 2020 (Avg. rating: 4.9)
• 12 Reviews on Sep 22, 2020 (Avg. rating: 4.8)
• 12 Reviews on Sep 23, 2020 (Avg. rating: 4.5)
• 11 Reviews on Sep 18, 2020 (Avg. rating: 4.6)
• 10 Reviews on Sep 26, 2020 (Avg. rating: 4.7)
• 9 Reviews on Sep 4, 2020 (Avg. rating: 5.0)
• 9 Reviews on Sep 25, 2020 (Avg. rating: 5.0)
• 9 Reviews on Sep 17, 2020 (Avg. rating: 4.4)
• 8 Reviews on Sep 3, 2020 (Avg. rating: 5.0)
• 8 Reviews on Sep 21, 2020 (Avg. rating: 4.5)
• 7 Reviews on Sep 2, 2020 (Avg. rating: 5.0)
• 7 Reviews on Sep 24, 2020 (Avg. rating: 4.7)
• 6 Reviews on Aug 9, 2020 (Avg. rating: 5.0)
• 6 Reviews on Sep 28, 2020 (Avg. rating: 5.0)
• 6 Reviews on Sep 27, 2020 (Avg. rating: 4.8)
Show All

In total, we found that 393 reviews were created on just 28 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 4.0. 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

• 
• 5%
• have only posted one review

37 of the 737 reviewers have only reviewed this product. The One-Hit Wonders have rated this product an average of 3.0 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.

Single-Day Reviewers

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

11 of the 737 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 3.7 while all other reviewers 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 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 4.4, while the average ease score for reviewers in this category is 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.

• 
• 21%
• Used substantial repetitive phrases

153 of the 737 total reviews for this product use substantial repetitive phrases between them. These reviewers have rated this product an average of 4.9 while reviews without substantial repetitive phrases rated this product an average of 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.

Read more about our Phrase Repetition test.

• 
• 21%
• Substantial overlapping review history

156 of the 737 reviewers have substantial overlapping product review history. These reviewers have rated this product an average of 4.7 while the reviewers who have a more unique product review history 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.

Read more about our Overlapping Review History test.

• 
• 47%
• 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 2 groups with a statistically significant greater concentration than what we'd expect to see:

• 0-5 words: 22.8% (Avg. rating: 4.1)
• 41-65 words: 24.4% (Avg. rating: 4.8)

In total, we found that 348 reviews (or 47%) are within an overrepresented word count group. While this is more reviews from overrepresented word count groups than we'd expect to see, the discrepancy in ratings between reviews with overrepresented word groups and all other reviews isn’t significant enough to rule out the possibility of it being due to random chance.

Read more about our Word Count Comparison test.

• 
• 85%
• 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: 40.0% (Avg. rating: 4.2)
• Reviewers with 6-15 Reviews: 44.9% (Avg. rating: 4.6)

In total, we found that 626 reviewers (or 85%) are within an overrepresented participation group. This is an excessively high number of reviewers in overrepresented participation groups.

Read more about our Reviewer Participation test.

• 
• 3%
• Unverified Purchases

20 of the 737 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.

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

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.