• 1
• Review has been deleted

We discovered a total of 1 deleted Review 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

• 
• 43%
• Created over 10 days

We counted 1,227 reviews for this product over the span of 4,103 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 10 days exceeding this threshold:

• 406 Reviews on Sep 8, 2009 (Avg. rating: 4.5)
• 55 Reviews on Sep 7, 2009 (Avg. rating: 4.4)
• 23 Reviews on Sep 9, 2009 (Avg. rating: 4.4)
• 12 Reviews on Sep 11, 2009 (Avg. rating: 4.8)
• 9 Reviews on Sep 10, 2009 (Avg. rating: 5.0)
• 7 Reviews on Dec 7, 2009 (Avg. rating: 4.1)
• 5 Reviews on Aug 31, 2009 (Avg. rating: 4.8)
• 5 Reviews on Sep 5, 2009 (Avg. rating: 4.8)
• 4 Reviews on Oct 22, 2013 (Avg. rating: 5.0)
• 4 Reviews on Jan 12, 2010 (Avg. rating: 4.5)
Show All

In total, we found that 530 reviews were created on just 10 days. This is an excessively high number of reviews submitted on these high volume days.

Read more about our Rating Trend test.

• 
• 64%
• Unverified Purchases

790 of the 1,227 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

• 
• 43%
• Reviewed other products from this brand

524 of the 1,227 reviewers have reviewed other products for this brand. While this is more Brand Repeaters than we'd expect to see, it does not appear to have a significant impact on the overall rating.

Brand Loyalists

• 
• 3%
• Reviewed mostly products from this brand

39 of the 1,227 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.

Never-Verified Reviewers

• 
• 21%
• have zero verified purchases

257 of the 1,227 reviewers have never written a verified purchase review. While this is more Never-Verified Reviewers than we'd expect to see, it does not appear to have a significant impact on the overall rating.

Take-Back Reviewers

• 
• 30%
• have previously deleted reviews

367 of the 1,227 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.

• 
• 48%
• Used substantial repetitive phrases

591 of the 1,227 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.

• 
• 71%
• From reviewers with an overrepresented participation

We see the following 3 participation groups with a statistically significant greater concentration than what we'd expect to see:

• Reviewers with 1-5 Reviews: 21.8% (Avg. rating: 4.5)
• Reviewers with 6-15 Reviews: 32.5% (Avg. rating: 4.5)
• Reviewers with 16-30 Reviews: 16.4% (Avg. rating: 4.5)

In total, we found that 867 reviewers (or 71%) 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.

• 
• 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.

• 
• 29%
• Substantial overlapping review history

359 of the 1,227 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 4.4, while the average ease score for reviewers in this category is 4.4.

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

4 of the 1,227 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.