What Happened
More product info
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Report Card
Most Trusted Reviews
TRUST
- Verified Purchaser
- Take-Back Reviewer (6 deleted Reviews; avg. rating: 4.8)
- Easy Grader (avg. rating: 4.4)
Least Trusted Reviews
TRUST
- Unverified Purchaser
- Created on a high volume day
- Never-Verified Reviewer
- Take-Back Reviewer (2 deleted Reviews; avg. rating: 3.0)
- Overlapping Review History: reviewed 1 of 9 top products
- Critical Reviewer (avg. rating: 3.9)
Analysis Details
We discovered a total of 1,474 deleted Reviews for this product, with an average rating of 2.4. 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:
- 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.
- We have no information on reviews that were never published in the first place.
- 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.
861 of the 11,150 total reviews for this product are unverified purchases. The unverified purchasers have rated this product an average of 1.4 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.
Never-Verified Reviewers
Less than approximately 10% of reviewers have never written a verified purchase review. The Never-Verified Reviewers have rated this product an average of 1.0 while the reviewers who have written at least one verified purchase review rated this product an average of 3.5. 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.
Take-Back Reviewers
Approximately 35% of 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.
(5.0/5)
(5.0/5)
(3.7/5)
(5.0/5)
(2.7/5)
(5.0/5)
(5.0/5)
(4.0/5)
(5.0/5)
(5.0/5)
Approximately 80% of reviews use substantial repetitive phrases between them. This is an excessively large percentage which may indicate unnatural reviews.
Read more about our Rating Trend test.
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- <10%
- Have an overrepresented word count
Read more about our Word Count Comparison test.
~40% also reviewed:
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~35% also reviewed:
The Art of Loving by Erich Fromm
~25% also reviewed:
The Hidden Reality: Parallel Universes and the... by Brian Greene
~25% also reviewed:
A Grief Observed by C. S. Lewis [Harper One,2009]... by C. S. Lewis
~20% also reviewed:
Waking Up: A Guide to Spirituality Without... by Sam Harris
~20% also reviewed:
God and Stephen Hawking: Whose Design Is It... by John Lennox
~20% also reviewed:
Inherit the Wind: The Powerful Courtroom Drama in... by Jerome Lawrence
~20% also reviewed:
Borderlands / La Frontera: The New Mestiza by Gloria Anzaldúa
Less than approximately 10% of 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.
4.0 Product's Average Ease Score
4.3 Category's Average Ease Score
Read more about our Reviewer Ease test.
Brand Repeaters
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- <10%
- Admitted to receiving an incentive
Read more about our Incentivized Reviews test. Check out our study showing that Incentivized Reviewers are much more likely to leave a positive review.