The impact of electronic word-of-mouth (e-WOM) is huge. We know that. A recent article published in Science by Lev Muchnik, Sinan Aral and Sean Taylor confirms that our opinions are largely influenced by on-line comments. This also raises the issue of fake reviews.
A randomized experiment with more than 300,000 ratings over five months.
Prior ratings from others (here 'write comments in response to posted articles') create significant bias in its own individual rating behavior. More specifically:
- If the first comment was positive, this comment significantly increases the immediate likelihood of positive ratings by 32%, and leads to a 25% increase in the mean rating over the five months.
- If the first comment was negative, there was a higher probability that subsequent comments would be negative, relative to the control. However, over the five months, this was offset by a larger “correction effect” so that the negative effect was neutralized.
"Because the negative feedback doesn’t snowball, but the positive feedback does, increased turnout for providing UGC or ratings only seems to help on net. So yes, soliciting feedback would prove to be on average universally good for these companies"
“For businesses there is clearly an incentive to manipulate the ratings, especially early on. Because you get this 25% increase in the mean rating of the item with a single positive up vote of the item. And that is a big marginal change in a final score from a single action at the beginning.”