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Canon 100mm
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From Canon
This report was last updated 3/21/2017.
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Report Info:
Last Updated: Mar 21, 2017
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Note: While Amazon.com claims 406 Ratings, we counted 303 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
Brand Repeats

FAIL
Suspicious Reviewers

FAIL
Reviewer Ease

WARN
Phrase Repetition

WARN
Reviewer Participation

PASS
Rating Trend

PASS
Unverified Purchases

PASS
Word Count Comparison

PASS
Overlapping Review History

PASS
Incentivized Reviews

Most Trusted Reviews
This is a fantastic lens not only for Macro shots ... [Go to full review]
Aug 26, 2006
100%
TRUST
TRUST
-
Unverified Purchaser
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Critical Reviewer (avg. rating: 2.3)
Least Trusted Reviews
This is an AMAZING lens! The images are really sharp, ... [Go to full review]
Jul 10, 2014
0%
TRUST
TRUST
-
Verified Purchaser
-
Contains repetitive phrases (
show)
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Brand Repeater (3 of 33 reviews for this brand; avg rating: 5.0)
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Overlapping Review History: reviewed 1 of 9 top products
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Overrepresented Participation (posted 33 Reviews)
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Easy Grader (avg. rating: 4.3)
Analysis Details
Fail
Deleted Reviews

We discovered a total of 102 deleted Reviews for this product, with an average rating of 4.9. 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
Brand Repeats

Brand Repeaters
107 of the 303 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
30 of the 303 reviewers have reviewed multiple products but half or more of their reviews are for this brand. This is an excessively large percentage of Brand Loyalists which may indicate unnatural reviews.
Brand Monogamists
15 of the 303 reviewers have reviewed multiple products, but only for this brand. This is an excessively large percentage of Brand Monogamists which may indicate unnatural reviews.
Fail
Suspicious Reviewers

One-Hit Wonders
64 of the 303 reviewers have only reviewed this product. While this is more One-Hit Wonders than we'd expect to see, it does not appear to have a significant impact on the overall rating.
Take-Back Reviewers
118 of the 303 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.
Fail
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 4.5, while the average ease score for reviewers in this category is 4.2. 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.
4.5 Product's Average Ease Score
4.2 Category's Average Ease Score
Read more about our Reviewer Ease test.
Warn
Phrase Repetition

Reviews that contain one of these phrases are NOT necessarily devalued; read more about how this test works here.
Common Phrases in Reviews:
Show MoreShow Less
5 reviews
2 reviews
21 reviews
5 reviews
12 reviews
2 reviews
8 reviews
12 reviews
2 reviews
75 of the 303 total reviews for this product use substantial repetitive phrases between them. This is an excessively large percentage which may indicate unnatural reviews.
Warn
Reviewer Participation

-
- 57%
- 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:In total, we found that 173 reviewers (or 57%) are within an overrepresented participation group. This is an excessively high number of reviewers in overrepresented participation groups.
Pass
Rating Trend

-
- 1%
- Created over 1 day
We counted 303 reviews for this product over the span of 5,594 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 1 day exceeding this threshold:In total, we found that 3 reviews were created on just 1 day. This is within an acceptable range and it does not appear to be significantly affecting the overall rating for this product.
Pass
Unverified Purchases

88 of the 303 total reviews for this product are unverified purchases. This is within an acceptable range and it does not appear to be significantly affecting the overall rating for this product.
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.
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:
4% also reviewed:
TiffenUV Protection Filter by Tiffen
3% also reviewed:
Lowepro Lens Case 4S (Black) by Lowepro
3% also reviewed:
Transcend 8 GB Class 10 SDHC Flash Memory Card by Transcend
2% also reviewed:
Tiffen Circular Polarizer by Tiffen
2% also reviewed:
Amazon Basics Backpack for SLR Cameras and... by AmazonBasics
2% also reviewed:
SanDisk Extreme PRO 64GB SDXC Flash Memory Card... by SanDisk
2% also reviewed:
Transcend Information USB 3.0 Super Speed... by Transcend
2% also reviewed:
Giottos Rocket Air Blaster Large - Black by Giotto's
Does not include products
from the same brand
from the same brand
40 of the 303 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
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.