One-Hit Wonders

• 
• 11%
• have only posted one review

70 of the 662 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 4.8. 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

• 
• 6%
• have previously deleted reviews

38 of the 662 reviewers have had at least one of their past reviews for another product deleted. While this is more Take-Back Reviewers than we'd expect to see, it does not appear to have a significant impact on the overall rating.

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

• 
• 56%
• 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: 26.6% (Avg. rating: 4.9)
• 6-15 words: 29.5% (Avg. rating: 4.8)

In total, we found that 371 reviews (or 56%) are within an overrepresented word count group. These reviews have rated this product an average of 4.9, while all other reviews have rated this product an average of 4.8. 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 Word Count Comparison test.

• 
• 18%
• Created over 20 days

We counted 662 reviews for this product over the span of 1,082 days, an average of 0.6 reviews per day. If these reviews were created randomly, there would be a 99.9% chance that we would see 4 or fewer reviews on any given day.

However, we see the following 20 days exceeding this threshold:

• 9 reviews on Dec 7, 2014 (Avg. rating: 4.9)
• 8 reviews on Dec 5, 2014 (Avg. rating: 5.0)
• 8 reviews on Dec 9, 2014 (Avg. rating: 5.0)
• 7 reviews on Dec 13, 2014 (Avg. rating: 5.0)
• 7 reviews on Dec 6, 2014 (Avg. rating: 4.9)
• 7 reviews on Dec 27, 2014 (Avg. rating: 4.6)
• 7 reviews on Dec 18, 2014 (Avg. rating: 4.6)
• 6 reviews on Nov 21, 2014 (Avg. rating: 5.0)
• 6 reviews on Jan 5, 2015 (Avg. rating: 5.0)
• 6 reviews on Nov 17, 2014 (Avg. rating: 4.8)
• 6 reviews on Nov 23, 2014 (Avg. rating: 4.8)
• 5 reviews on Mar 10, 2015 (Avg. rating: 5.0)
• 5 reviews on Dec 19, 2014 (Avg. rating: 5.0)
• 5 reviews on Dec 12, 2014 (Avg. rating: 5.0)
• 5 reviews on Dec 8, 2014 (Avg. rating: 5.0)
• 5 reviews on Dec 4, 2014 (Avg. rating: 5.0)
• 5 reviews on Dec 16, 2014 (Avg. rating: 4.8)
• 5 reviews on Dec 14, 2014 (Avg. rating: 4.8)
• 5 reviews on Jan 1, 2015 (Avg. rating: 4.6)
• 5 reviews on Nov 29, 2014 (Avg. rating: 4.4)
Show All

In total, we found that 122 reviews were created on just 20 days. This is an excessively high number of reviews submitted on these high volume days.

Read more about our Rating Trend test.

• 
• 66%
• 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: 39.7% (Avg. rating: 4.9)
• Reviewers with 6-15 reviews: 26.6% (Avg. rating: 4.8)

In total, we found that 439 reviewers (or 66%) 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.

• 
• 6%
• Unverified Purchases

43 of the 662 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.

• 
• 3%
• Used substantial repetitive phrases

21 of the 662 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.

• 
• 17%
• Substantial overlapping review history

114 of the 662 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

• 
• 17%
• Reviewed other products from this brand

112 of the 662 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.

• 
• 1%
• Admitted to receiving an incentive

5 of the 662 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, or 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 the Deleted Reviews test here.