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iRobot Roomba 650 Vacuum Cleaning Robot Bundle with Replenishment Kit

Warn Unnatural reviews possible

Original:

4,117 Reviews

Adjusted:

2,928 Reviews

Rank in: Robotic Vacuums
81%
84%

View/Edit Adjustment
How is this calculated
Last Updated: 3/2/2017
Update Available
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Report Card

Click a test to jump to details

FAIL Suspicious Reviewers
FAIL Reviewer Ease
FAIL Phrase Repetition
FAIL Skewed Helpfulness
WARN Deleted Reviews
WARN Rating Trend
WARN Reviewer Participation
PASS Unverified Purchases
PASS Word Count Comparison
PASS Overlapping Review History
PASS Brand Repeats
PASS Incentivized Reviews

Other analysis for this product:

iRobot Vacuum Cleaning Robot - Roomba 650 From iRobot

Pass Reviews appear natural


Original:

67 Reviews


Adjusted:

50 Reviews

Most Trusted Reviews

this little guy runs great... good upgrade to the ancient ... [Go to full review]
Jan 12, 2017      
100% TRUST
  • Verified Purchaser
  • Take-Back Reviewer (4 deleted reviews; avg. rating: 5.0)
  • Easy Grader (avg. rating: 4.2)


Least Trusted Reviews

Does a great job. [Go to full review]
Dec 27, 2016      
0% TRUST
  • Verified Purchaser
  • Created on a high volume day
  • Contains repetitive phrases (show)
  • Single-Day Reviewer (posted all reviews on Dec 27, 2016)
  • Overrepresented Participation (posted 3 reviews)
  • Critical Reviewer (avg. rating: 4.0)


Analysis Details

Note: While Amazon claims 4,117 reviews, we counted 4,115 available on their site.

Fail Suspicious Reviewers

One-Hit Wonders


506 of the 4,115 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.

from one-hit wonders

from reviewers with more than one review


4.4
4.5


Take-Back Reviewers


1,075 of the 4,115 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.

from take-back reviewers

from reviewers without previously deleted reviews


4.5
4.4


Single-Day Reviewers


305 of the 4,115 reviewers have written multiple reviews but posted all of them on a single day. The Single-Day reviewers have rated this product an average of 4.6 while all other reviewers 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.

from single-day reviewers

from non-single-day reviewers


4.6
4.4


Read more about our Suspicious Reviewers test.

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

4.2 Product's Average Ease Score

4.1 Category's Average Ease Score


4.2
4.1


Read more about our Reviewer Ease test.


Fail 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:
186 reviews
(4.5%)


34 of the 4,115 total reviews for this product use substantial repetitive phrases between them. These reviewers have rated this product an average of 4.8 while reviews without substantial repetitive phrases rated this product an average of 4.5. 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.

from reviews with substantial repetitive phrases

from reviews without substantial repetitive phrases


4.8
4.5


Read more about our Phrase Repetition test.

Fail Skewed Helpfulness
We examined the average net helpfulness score of negative reviews against the average net helpfulness score of positive reviews. The net helpfulness score is the number of times a review has been marked as helpful minus the number of times a review has been marked as unhelpful. We found that the negative reviews had an average net helpfulness score of -2.9 while the positive reviews had an average net helpfulness score of -0.5. Based on our statistical modeling, this discrepancy is significant enough to believe that the difference is not due to random chance, but possibly due to influence of unnatural voting patterns.

Example critical reviews

-0.5 average net helpfulness for positive reviews

-2.9 average net helpfulness for negative reviews


Read more about our Skewed Helpfulness test.


Warn Deleted Reviews

We discovered a total of 7 deleted reviews for this product, with an average rating of 3.6. 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.

3.6 average rating of deleted reviews

3.6



Read more about our Deleted Reviews test.

Warn Rating Trend

  • 18%
  • Created over 53 days

We counted 4,115 reviews for this product over the span of 1,632 days, an average of 2.5 reviews per day. If these reviews were created randomly, there would be a 99.9% chance that we would see 9 or fewer reviews on any given day.

However, we see the following 53 days exceeding this threshold:In total, we found that 738 reviews were created on just 53 days. This is an excessively high number of reviews submitted on these high volume days.

from reviews created on high volume days

from reviews created on normal volume days


4.4
4.5


Read more about our Rating Trend test.

Warn Reviewer Participation

  • 83%
  • 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:In total, we found that 3421 reviewers (or 83%) are within an overrepresented participation group. This is an excessively high number of reviewers in overrepresented participation groups.

From reviewers with an overrepresented participation

From reviewers with a properly represented participation


4.4
4.6


Read more about our Reviewer Participation test.

Pass Unverified Purchases

431 of the 4,115 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.

from unverified purchasers

from verified purchases


4.2
4.5


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.

Pass Overlapping Review History


122 of the 4,115 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.

from reviewers with substantial overlapping history

from reviewers without a substantial overlapping history


4.6
4.5


Read more about our Overlapping Review History test.

Pass Brand Repeats

Brand Repeaters

We didn't detect a substantial amount of Brand Repeaters.

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.


1 of the 4,115 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.

from incentivized reviews

from non-incentivized reviews


5.0
4.5


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