'Word of mouth' advertising is valuable because marketing groups know that opinions of friends and associates count more than the paid endorsements of strangers. But what kind of opinions matter most? It turns out the negative ones do, even if someone had privately had a positive impression prior to the negative input.

“Consumer attitudes toward products and services are frequently influenced by others around them. Social networks, such as those found on Myspace and Facebook suggest that these influences will continue to be significant drivers of individual consumer attitudes as society becomes more inter-connected,” explain Adam Duhachek, Shuoyang Zhang, and Shanker Krishnan of Indiana University in a Journal of Consumer Research report. “Our research seeks to understand the conditions where group influence is strongest.”

Consumers were presented with information about a new product and allowed to independently form their evaluations. As would be normally expected with many products, some of these evaluations were positive and others negative. The researchers then revealed to participants whether their peers evaluated the product negatively or positively.

They found that the opinions of others exert especially strong influence on individual attitudes when these opinions are negative. Additionally, consumers that privately held positive attitudes toward the product were more susceptible to influence from group opinion than those who initially held negative opinions.

Furthermore, the researchers also found that those with negative opinions of the product were likely to become even more negative if asked to participate in a group discussion: “When consumers expect to interact with other consumers through these forums, learning the views of these other consumers may reinforce and even polarize their opinions, making them more negative,” the researchers reveal.

“This research has several interesting implications. First, given the strong influence of negative information, marketers may need to expend extra resources to counter-act the effects of negative word of mouth in online chatrooms, blogs and in offline media. Conversely, companies could damage the reputations of competitors by disseminating negative information online,” the researchers explain. “Consumers should be aware that these social influence biases exist and are capable of significantly impacting their perceptions.”

Adam Duhachek, Shuoyang Zhang, and Shanker Krishnan, “Anticipated Group Interaction: Coping with Valence Asymmetries in Attitude Shift.” Journal of Consumer Research: October 2007.