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From Robert Reed
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Report Info:
Note: While Amazon.com claims 66 Ratings, we counted 60 Reviews available on their site.
Note: We only analyze "reviews" and ignore one-tap "ratings".
Note: We only analyze "reviews" and ignore one-tap "ratings".
Report Card
Warn Overall Grade
FAIL
Deleted Reviews

FAIL
Unverified Purchases

FAIL
Suspicious Reviewers

WARN
Phrase Repetition

PASS
Rating Trend

PASS
Word Count Comparison

PASS
Overlapping Review History

PASS
Reviewer Participation

PASS
Reviewer Ease

PASS
Brand Repeats

PASS
Incentivized Reviews

Most Trusted Reviews
An epic space opera. Intriguing characters and situations, all in ... [Go to full review]
Jul 11, 2014
100%
TRUST
TRUST
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Verified Purchaser
-
Overlapping Review History: reviewed 1 of 9 top products
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Easy Grader (avg. rating: 4.3)
Least Trusted Reviews
Marrow is my first Robert Reed novel, but from what ... [Go to full review]
Apr 19, 2009
0%
TRUST
TRUST
-
Unverified Purchaser
-
Contains repetitive phrases (
show)
-
Never-Verified Reviewer
-
Take-Back Reviewer (1 deleted Review; avg. rating: 4.0)
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Overlapping Review History: reviewed 3 of 9 top products
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Critical Reviewer (avg. rating: 3.8)
Analysis Details
Fail
Deleted Reviews

We discovered a total of 7 deleted Reviews for this product, with an average rating of 1.9. 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.
Fail
Unverified Purchases

37 of the 60 total reviews for this product are unverified purchases. The unverified purchasers have rated this product an average of 3.4 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.
Fail
Suspicious Reviewers

Never-Verified Reviewers
12 of the 60 reviewers have never written a verified purchase review. The Never-Verified Reviewers have rated this product an average of 2.7 while the reviewers who have written at least one verified purchase review 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.
Take-Back Reviewers
25 of the 60 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.
Warn
Phrase Repetition

Reviews that contain one of these phrases are NOT necessarily devalued; read more about how this test works here.
12 of the 60 total reviews for this product use substantial repetitive phrases between them. This is an excessively large percentage which may indicate unnatural reviews.
Pass
Rating Trend

-
- 0%
- Created on high-volume days
We counted 60 reviews for this product over the span of 6,385 days, an average of 0.0 reviews per day. If these reviews were created randomly, there would be a 99.9% chance that we would see 1 or fewer reviews on any given day. We didn't find any days exceeding this threshold.
Read more about our Rating Trend test.
Read more about our Rating Trend test.
Pass
Word Count Comparison

-
- 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.
Read more about our Word Count Comparison test.
Pass
Overlapping Review History

Reviewers of this product have ALSO reviewed the following products:
12% also reviewed:
Seveneves by Neal Stephenson
10% also reviewed:
We Are Legion (We Are Bob) (Bobiverse) (Volume 1) by Dennis E. Taylor
8% also reviewed:
The Engines of God by Ace
8% also reviewed:
Century Rain (Revelation Space) by Alastair Reynolds
8% also reviewed:
The Prefect (Revelation Space) by Alastair Reynolds
8% also reviewed:
Stranger in a Strange Land by Robert A. Heinlein
8% also reviewed:
Spin by Robert Charles Wilson
8% also reviewed:
The Martian: Classroom Edition: A Novel by Andy Weir
8% also reviewed:
Frito-Lay 18 Piece VP Baked & Popped Mix,... by Frito Lay
26 of the 60 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.
Pass
Reviewer Participation

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- 0%
- From reviewers with an overrepresented participation
We didn't find any participation groups that had a statistically significant greater concentration than what we'd expect to see in this category.
Read more about our Reviewer Participation test.
Read more about our Reviewer Participation test.
Pass
Reviewer Ease

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, while the average ease score for reviewers in this category is 4.3.
4.0 Product's Average Ease Score
4.3 Category's Average Ease Score
Read more about our Reviewer Ease test.
Pass
Brand Repeats

Brand Repeaters
3 of the 60 reviewers have reviewed other products for this brand. This is within an acceptable range and it does not appear to be significantly affecting the overall rating for this product.
Pass
Incentivized Reviews

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.
Read more about our Incentivized Reviews test. Check out our study showing that Incentivized Reviewers are much more likely to leave a positive review.