• 223
• Reviews have been deleted

We discovered a total of 223 deleted Reviews for this product, with an average rating of 5. 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

• 
• 44%
• Created over 17 days

We counted 142 reviews for this product over the span of 1,576 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 17 days exceeding this threshold:

• 6 Reviews on Feb 9, 2017 (Avg. rating: 5.0)
• 5 Reviews on Dec 26, 2016 (Avg. rating: 5.0)
• 5 Reviews on Jan 3, 2017 (Avg. rating: 4.2)
• 4 Reviews on Dec 20, 2016 (Avg. rating: 5.0)
• 4 Reviews on Dec 27, 2016 (Avg. rating: 5.0)
• 4 Reviews on Jan 4, 2017 (Avg. rating: 5.0)
• 4 Reviews on Jan 16, 2017 (Avg. rating: 5.0)
• 4 Reviews on Jan 2, 2017 (Avg. rating: 4.3)
• 3 Reviews on Dec 19, 2016 (Avg. rating: 5.0)
• 3 Reviews on Jan 9, 2017 (Avg. rating: 5.0)
• 3 Reviews on Jan 15, 2017 (Avg. rating: 5.0)
• 3 Reviews on Dec 22, 2016 (Avg. rating: 4.7)
• 3 Reviews on Dec 28, 2016 (Avg. rating: 4.7)
• 3 Reviews on Jan 12, 2017 (Avg. rating: 4.7)
• 3 Reviews on Dec 18, 2016 (Avg. rating: 4.0)
• 3 Reviews on Feb 12, 2017 (Avg. rating: 3.3)
• 3 Reviews on Feb 26, 2017 (Avg. rating: 3.3)
Show All

In total, we found that 63 reviews were created on just 17 days. The reviews on these high volume days have rated this product an average of 4.6 while reviews from other days have rated this product an average of 4.1. 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.

• 
• 41%
• Unverified Purchases

58 of the 142 total reviews for this product are unverified purchases. The unverified purchasers have rated this product an average of 4.8 while the verified purchasers have rated this product an average of 4.1. 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.

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.

Take-Back Reviewers

• 
• 85%
• have previously deleted reviews

121 of the 142 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 4.5 while the reviewers who don't have any deleted reviews in their history have rated this product an average of 3.7. 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.

• 
• 25%
• 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:

• 41-65 words: 25.4% (Avg. rating: 4.8)

In total, we found that 36 reviews (or 25%) are within an overrepresented word count group. These reviews have rated this product an average of 4.8, while all other reviews 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 Word Count Comparison test.

• 
• 62%
• Substantial overlapping review history

88 of the 142 reviewers have substantial overlapping product review history. These reviewers have rated this product an average of 4.8 while the reviewers who have a more unique product review history rated this product an average of 3.6. 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.

• 
• 48%
• 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 31-50 Reviews: 21.1% (Avg. rating: 4.5)
• Reviewers with 51-100 Reviews: 26.8% (Avg. rating: 4.7)

In total, we found that 68 reviewers (or 48%) are within an overrepresented participation group. These reviews have rated this product an average of 4.6, while all other reviews have rated this product an average of 4.1. 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 Reviewer Participation test.

Brand Repeaters

• 
• 60%
• Reviewed other products from this brand

85 of the 142 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.

Read more about our Brand Repeats 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 4.4. While this discrepancy is rather large, it is not quite large enough to rule out the possibility of it being due random chance.

• 
• 23%
• Used substantial repetitive phrases

32 of the 142 total reviews for this product use substantial repetitive phrases between them. This is an excessively large percentage which may indicate unnatural reviews.

Read more about our Phrase Repetition 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.