Single-Day Reviewers

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

6 of the 1,086 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 4.7. 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.

• 6
• Reviews have been deleted

We discovered a total of 6 deleted Reviews for this product, with an average rating of 4.8. 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

• 
• 7%
• Created over 17 days

We counted 1,086 reviews for this product over the span of 3,523 days, an average of 0.3 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 17 days exceeding this threshold:

• 7 Reviews on Dec 25, 2012 (Avg. rating: 4.3)
• 5 Reviews on Mar 14, 2017 (Avg. rating: 5.0)
• 5 Reviews on Sep 26, 2012 (Avg. rating: 4.8)
• 5 Reviews on Jan 2, 2013 (Avg. rating: 4.8)
• 5 Reviews on Jun 23, 2013 (Avg. rating: 4.2)
• 4 Reviews on Dec 28, 2012 (Avg. rating: 5.0)
• 4 Reviews on Jan 17, 2017 (Avg. rating: 5.0)
• 4 Reviews on Jan 24, 2017 (Avg. rating: 5.0)
• 4 Reviews on Mar 11, 2017 (Avg. rating: 5.0)
• 4 Reviews on Aug 2, 2017 (Avg. rating: 5.0)
• 4 Reviews on Dec 8, 2012 (Avg. rating: 4.8)
• 4 Reviews on May 18, 2013 (Avg. rating: 4.5)
• 4 Reviews on Nov 13, 2014 (Avg. rating: 4.5)
• 4 Reviews on Feb 9, 2017 (Avg. rating: 4.5)
• 4 Reviews on Oct 3, 2012 (Avg. rating: 4.3)
• 4 Reviews on Oct 27, 2014 (Avg. rating: 4.3)
• 4 Reviews on Nov 29, 2012 (Avg. rating: 4.0)
Show All

In total, we found that 75 reviews were created on just 17 days. Although any days with a larger number of reviews than expected is suspicious, these reviews do not appear to have a significant impact on the overall rating.

Read more about our Rating Trend test.

• 
• 62%
• Unverified Purchases

675 of the 1,086 total reviews for this product are unverified purchases. While this is a higher percentage of unverified purchases than we'd expect to see, it does not appear to have a significant impact on the overall rating.

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.

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 4.3. While this discrepancy is rather large, it is not quite large enough to rule out the possibility of it being due random chance.

• 
• 58%
• 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: 57.6% (Avg. rating: 4.7)

In total, we found that 626 reviews (or 58%) are within an overrepresented word count group. This is an excessively high number of reviews in overrepresented word count groups.

Read more about our Word Count Comparison test.

• 
• 18%
• Used substantial repetitive phrases

191 of the 1,086 total reviews for this product use substantial repetitive phrases between them. While this is more than we'd expect to see, the discrepancy in ratings between the these reviews and reviews without substantial repetitive phrases isn't significant enough to rule out the possibility of it being due to random chance.

Read more about our Phrase Repetition test.

• 
• 70%
• 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: 34.4% (Avg. rating: 4.7)
• Reviewers with 6-15 Reviews: 35.4% (Avg. rating: 4.7)

In total, we found that 757 reviewers (or 70%) 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.

• 
• 4%
• Substantial overlapping review history

46 of the 1,086 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

• 
• 4%
• Reviewed other products from this brand

41 of the 1,086 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.

• 
• 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.