• 284
• Reviews have been deleted

We discovered a total of 284 deleted Reviews for this product, with an average rating of 4.1. 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

One-Hit Wonders

• 
• 17%
• have only posted one review

160 of the 943 reviewers have only reviewed this product. The One-Hit Wonders have rated this product an average of 4.3 while the reviewers who have posted more than one review 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.

Never-Verified Reviewers

• 
• 42%
• have zero verified purchases

399 of the 943 reviewers have never written a verified purchase review. The Never-Verified Reviewers have rated this product an average of 4.2 while the reviewers who have written at least one verified purchase review 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.

Take-Back Reviewers

• 
• 29%
• have previously deleted reviews

269 of the 943 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.

• 
• 24%
• 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:

• 101-200 words: 24.2% (Avg. rating: 4.2)

In total, we found that 228 reviews (or 24%) are within an overrepresented word count group. These reviews have rated this product an average of 4.2, while all other reviews 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 Word Count Comparison test.

• 
• 14%
• Created over 34 days

We counted 943 reviews for this product over the span of 7,201 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 34 days exceeding this threshold:

• 9 Reviews on Oct 15, 2000 (Avg. rating: 5.0)
• 8 Reviews on Sep 1, 2014 (Avg. rating: 4.0)
• 7 Reviews on Oct 17, 2001 (Avg. rating: 3.7)
• 5 Reviews on Oct 16, 2000 (Avg. rating: 4.6)
• 5 Reviews on Jan 2, 2001 (Avg. rating: 3.6)
• 4 Reviews on Oct 23, 2000 (Avg. rating: 5.0)
• 4 Reviews on Dec 12, 2000 (Avg. rating: 4.8)
• 4 Reviews on Oct 28, 2000 (Avg. rating: 4.8)
• 4 Reviews on Nov 11, 2000 (Avg. rating: 4.8)
• 4 Reviews on Jan 5, 2001 (Avg. rating: 4.5)
• 4 Reviews on Oct 22, 2000 (Avg. rating: 4.5)
• 4 Reviews on Nov 29, 2000 (Avg. rating: 3.8)
• 3 Reviews on Oct 13, 2000 (Avg. rating: 5.0)
• 3 Reviews on Oct 29, 2000 (Avg. rating: 5.0)
• 3 Reviews on Nov 12, 2000 (Avg. rating: 5.0)
• 3 Reviews on Oct 24, 2000 (Avg. rating: 5.0)
• 3 Reviews on Oct 21, 2000 (Avg. rating: 5.0)
• 3 Reviews on Nov 1, 2000 (Avg. rating: 4.7)
• 3 Reviews on Oct 14, 2000 (Avg. rating: 4.7)
• 3 Reviews on Nov 11, 2001 (Avg. rating: 4.7)
• 3 Reviews on Jan 20, 2002 (Avg. rating: 4.7)
• 3 Reviews on Aug 4, 2014 (Avg. rating: 4.3)
• 3 Reviews on Oct 25, 2000 (Avg. rating: 4.0)
• 3 Reviews on Oct 17, 2000 (Avg. rating: 4.0)
• 3 Reviews on Feb 28, 2002 (Avg. rating: 4.0)
• 3 Reviews on Dec 8, 2000 (Avg. rating: 4.0)
• 3 Reviews on Dec 20, 2000 (Avg. rating: 3.7)
• 3 Reviews on Aug 23, 2001 (Avg. rating: 3.7)
• 3 Reviews on Nov 2, 2002 (Avg. rating: 3.7)
• 3 Reviews on Jan 7, 2008 (Avg. rating: 2.7)
• 3 Reviews on Dec 11, 2007 (Avg. rating: 2.3)
• 3 Reviews on Jul 21, 2001 (Avg. rating: 2.0)
• 3 Reviews on Nov 22, 2000 (Avg. rating: 1.7)
• 3 Reviews on Dec 4, 2007 (Avg. rating: 1.0)
Show All

In total, we found that 128 reviews were created on just 34 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.

• 
• 72%
• Unverified Purchases

677 of the 943 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.

Brand Repeaters

• 
• 27%
• Reviewed other products from this brand

252 of the 943 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 943 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, the discrepancy in ratings between the Brand Loyalists and non-loyalists isn't significant enough to rule out the possibility of it being due to random chance.

Read more about our Brand Repeats test.

• 
• 27%
• Used substantial repetitive phrases

256 of the 943 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.

• 
• 64%
• 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: 37.3% (Avg. rating: 4.1)
• Reviewers with 6-15 Reviews: 26.3% (Avg. rating: 4.0)

In total, we found that 600 reviewers (or 64%) 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.

• 
• 37%
• Substantial overlapping review history

349 of the 943 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.

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 4.1, while the average ease score for reviewers in this category is 4.3.

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

1 of the 943 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. Check out our study showing that Incentivized Reviewers are much more likely to leave a positive review.