That review you wrote on Amazon? Priceless

Research shows that a 5-star rating isn't actually the best, as if customers don't see at least a few negative reviews they think the system's been gamed. SAN FRANCISCO -- Chances are, a week or two after you buy something online you'll get an email asking, "How'd we do?" and a link to review the product. Your response and those of other customers are worth a lot: $400 billion, according to one analyst. The more buys, the more reviews. The more buys, the higher your rank in search and the more sales you get," said Alice Kim, owner of online cosmetic brand Elizabeth Mott. Even a single comment can make a huge difference. Just going from zero review to one increases the rate at which online window-shoppers actually click the "buy" button by 65%, said Matt Moog, CEO of Power Reviews, a company that makes ratings and review software. He estimates 20% of sales are driven by reviews and one-third of online shoppers say straight out they won't buy a product that hasn't been positively reviewed. Increasingly, online reviews matter for all buyers even though online sales made up just 8.3% of U.S. retail sales in the fourth quarter, according to the Department of Commerce -- and Amazon's reviews matter most of all. The online retailer lives and dies by its reviews online, said owner Alice Kim. Fifty-five percent of shoppers start their buying research on Amazon, a survey by marketing firm BloomReach found, and half of all shoppers say they rely primarily on Amazon for reviews, according to Market Track, an e-commerce analysis firm. "They can be in Best Buy or Home Depot, but they go on their phones to check Amazon reviews," said Greg Perry of One Click Retail, an e-commerce data company. Amazon's reviews rank so highly in part because they're considered the most trustworthy, even though -- like other sites -- it's not immune from people using the reviews for ancillary purposes, say last November's flood of one-star reviews of anchor Megyn Kelly's book hours after it went on sale, which the LA Times said was orchestrated by a pro-Trump forum on Reddit. The Seattle retailer has gone to great lengths to root out fake reviews, launching over 1,000 lawsuits against those who post them, according to the company. It also marks and gives more weight to reviews by people who actually bought the product and has introduced a machine learning algorithm that gives more weight to newer, more helpful reviews. In October Amazon began requiring that any review of a product given to the reviewer for free or at reduced cost be marked as such. "Our focus is to make sure our reviews are authentic and helpful," said spokeswoman Angie Newman. Whether consumers realize it or not, the notes they hastily type out, whether glowing or scathing, wield tremendous power. "Before, you might have told ten people about a product.