More Than Half the Reviews For Certain Popular Products on Amazon Are Questionable, Outside Auditors Say. Amazon Disputes Those Estimates. (npr.org)

NPR has an interesting story, full of anecdotes, that looks into several growing marketplaces where reviews for Amazon products are bought and paid for. From the story: "Our approximation is that less than 1 percent of reviews are inauthentic," says Sharon Chiarella, vice president of community shopping at Amazon. She adds that "sometimes individual products have more suspicious activity." [...] Chiarella says the lawsuits give the company the opportunity to subpoena bad actors to get data from them. "That allows us to identify more bad actors and spider out from there and train our algorithms," she says. But this has led to a sort of digital cat-and-mouse game. As Amazon and its algorithms get better at hunting them down, paid reviewers employ their own evasive maneuvers. Travis, the teenage paid reviewer, explained his process.

He's a member of several online channels where Amazon sellers congregate, hawking Ethernet cables, flashlights, protein powder, fanny packs -- any number of small items for which they want favorable reviews. If something catches Travis' attention, he approaches the seller and they negotiate terms. Once he buys the product and leaves a five-star review, the seller will refund his purchase, often adding a few dollars "commission" for his trouble. He says he earns around $200 a month this way. The sellers provide detailed instructions, to avoid being detected by Amazon's algorithms, Travis says. For example, he says, "Order here at the Amazon link. Don't clip any coupons or promo codes. [Wait 4 to 5 days] after receiving [the item]." This last instruction is especially important, Travis adds. "If you review too soon after receiving it'll look pretty suspicious."

Comments

Correct..what to do

[110010001000]

This is accurate. There are way too many five star reviews. If you want to look at real reviews, look at the 3 star ones that have comments. They are usually balanced reviews. No product is five star perfect. Even a 4 star review is suspect. What amazon should have is a scale from 1 to 10. The spammers will always choose 9 or 10.

Ha, they tried even more on me!

[Ecuador]

I am a top-500 reviewer on Amazon.co.uk, so my reviews generally show up high quickly (ok, maybe not because of ranking just by upvotes - haven't looked into how it works). I try to review things I know a lot about, so I wrote some (very accurate, technical and detailed, but bad) reviews on some binoculars (also put them in a blog post here, helpful for people buying binoculars on Amazon) that were highly rated and/or top sellers, but were of unknown branding or had ridiculous specs (30x60 pocket binoculars).
So, on some listings my bad reviews which came on top, started getting bursts of downvotes. Like 10 a day. A person actually contacted me to tell me he belonged to a FB group of the seller where they would get free stuff to review. The seller told the group I am a lying competitor and gave them links to my reviews for downvoting (hence the bursts). The person who contacted me looked into my reviews instead and figured out I was just a knowledgeable reviewer and even sent me screenshots of the FB threads. I forwarded the info to Amazon and they didn't do anything. Well, in fact, I can no longer find the review that had offended that seller the most, so maybe they did something in the end :)
Additionally, a seller (the same if I remember correctly) wrote me and told me they had reported me to Amazon for malicious reviews. They left comments under my reviews saying that I am a competitor who owns Agena Astro (hilarious, that's a huge US astro retailer!). I also brought that crap to Amazon's attention, they didn't seem to mind.
In all, I love Amazon, I've been a Prime subscriber for over a decade mainly because their customer service is second to none...
But that customer service is only stellar when it comes to you buying/returning etc stuff, they don't really seem to care about marketplace sellers going rogue. Which is a shame, back a decade ago most of the stuff was sold by Amazon and the reviews were a surefire way to find what is good and what is not. Nowadays, you can't trust them. And it's not just the shady reviewers, even some that Amazon itself picks (Vine) are obviously clueless about most of the stuff they review and how legit are your reviews anyway when you do several per day?
So, you still get easy returns/refunds etc, but you can no longer rely on the reviews - probably with the exception of something sold only by Amazon.