• 926
• Reviews have been deleted

We discovered a total of 926 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 the Deleted Reviews test here.

Show distribution of deleted reviews

• 
• 43%
• Unverified Purchases

438 of the 1,024 total reviews for this product are unverified purchases. The unverified purchasers have rated this product an average of 4.6 while the verified purchasers have 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.

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

• 
• 29%
• have previously deleted reviews

297 of the 1,024 reviewers have had at least one of their past reviews for another product deleted. This is an excessively large percentage of Take-Back Reviewers which may indicate 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 4.3. 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.

• 
• 5%
• Used substantial repetitive phrases

51 of the 1,024 total reviews for this product use substantial repetitive phrases between them. These reviewers have rated this product an average of 4.8 while reviews without substantial repetitive phrases 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 Phrase Repetition test.

• 
• 14%
• Substantial overlapping review history

147 of the 1,024 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 4.5. 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 Overlapping Review History test.

• 
• 13%
• Created over 16 days

We counted 1,024 reviews for this product over the span of 1,276 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 16 days exceeding this threshold:

• 14 reviews on Jan 16, 2018 (Avg. rating: 4.9)
• 14 reviews on Mar 16, 2015 (Avg. rating: 4.7)
• 9 reviews on Mar 24, 2015 (Avg. rating: 4.9)
• 9 reviews on May 20, 2015 (Avg. rating: 4.7)
• 9 reviews on Jun 1, 2015 (Avg. rating: 4.3)
• 8 reviews on Mar 28, 2015 (Avg. rating: 4.4)
• 7 reviews on Mar 13, 2015 (Avg. rating: 5.0)
• 7 reviews on Mar 17, 2015 (Avg. rating: 4.9)
• 7 reviews on Mar 31, 2015 (Avg. rating: 4.6)
• 7 reviews on May 31, 2015 (Avg. rating: 4.6)
• 7 reviews on Jul 3, 2017 (Avg. rating: 4.4)
• 7 reviews on Apr 20, 2015 (Avg. rating: 3.9)
• 6 reviews on Apr 25, 2015 (Avg. rating: 4.8)
• 6 reviews on Jun 7, 2015 (Avg. rating: 4.5)
• 6 reviews on Mar 26, 2015 (Avg. rating: 4.3)
• 6 reviews on Apr 29, 2015 (Avg. rating: 4.3)
Show All

In total, we found that 129 reviews were created on just 16 days. Although any days with a larger number of reviews than expected is suspicious, the discrepancy in ratings from reviews created on these high volume days and reviews created on other days isn't significant enough to rule out the possibility of it being due to random chance.

Read more about our Rating Trend test.

Brand Repeaters

• 
• 26%
• Reviewed other products from this brand

263 of the 1,024 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.

Brand Loyalists

• 
• 2%
• Reviewed mostly products from this brand

22 of the 1,024 reviewers have reviewed multiple products but half or more of their reviews are for this brand. While this is more Brand Loyalists than we'd expect to see, it does not appear to have a significant impact on the overall rating.

Read more about our Brand Repeats test.

• 
• 32%
• 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 1-5 reviews: 31.8% (Avg. rating: 4.6)

In total, we found that 326 reviewers (or 32%) are within an overrepresented participation group. While this is more reviews from overrepresented participation groups than we'd expect to see, the discrepancy in ratings between reviewers in an overrepresented participation groups and all other reviewers isn’t significant enough to rule out the possibility of it being due to random chance.

Read more about our Reviewer Participation test.

• 
• 0%
• Have an overrepresented word count

We didn't find any review word count groups that had a statistically significant greater concentration than what we'd expect to see in this category.
Read more about our Word Count Comparison test.

On Oct 3, 2016, Amazon prohibited incentivized reviews, however we still test for them since there are still millions in our dataset.

• 
• 2%
• Admitted to receiving an incentive

18 of the 1,024 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.