In his new book, The Hype Machine, MIT Sloan School of Management professor Sinan Aral takes on the greatest communications force of our lifetime: social media. Aral provides an insightful, level-headed, analysis of the power, peril, and potential of Twitter, Facebook, Instagram, and other social platforms for both organizations and society.

For the most part, consumers have faith in online ratings and view them as trustworthy. But, the author argues, this trust may be misplaced. The heart of the problem lies with our herd instincts -natural human impulses characterized by a lack of individual decision making -that cause us to think and act in the same way as other people around us. When it comes to online ratings, our herd instincts combine with our susceptibility to positive "social influence."When we see that other people have appreciated a certain book, enjoyed a hotel or restaurant or liked a particular doctor, this can cause us to feel the same positive feelings and to provide a similarly high online rating. The author describes an experiment that he and two colleagues conducted on a social news-aggregation website. On the site, users rate news articles and comments by voting them up or down based on how much they enjoyed them. The researchers randomly manipulated the scores of comments with a single up or down vote and then measured the impact of these small manipulations on subsequent scores. The results were striking. The positive manipulations created a positive social influence bias that persisted over five months and that ultimately increased the comments'final ratings by 25%. Negatively manipulated scores, meanwhile, were offset by a correction effect that neutralized the manipulation: Although viewers of negatively manipulated comments were more likely to vote negative (evidence of negative herding), they were even more likely to positively "correct"what they saw as an undeserved negative score.

Social influence marketing is a powerful tool--but understanding how influence actually works is more complicated than it might appear, because correlation and causation are easily confused. Robust analytics can help marketers get it right, enabling them to design effective campaigns and avoid costly mistakes.

Viral features embedded in your product can have an explosive effect on adoption. Automatic notifications, which are passive, get the most hits. But personalized features, such as user-to-user invitations, are three times as effective per message.

This is an MIT Sloan Management Review article. Although IT portfolio management has been a best practice for some time, many companies still generate substandard returns from their IT investments. Points out that investing the right amounts in the right IT asset classes is only the first step--a suite of interlocking business practices and processes collectively labeled "IT savvy" must complement IT portfolio management techniques. The benefits of establishing such practices add up to a tangible IT savvy premium: higher net profits and other performance gains. Cites a range of organizations in which IT savvy is ingrained, informing many of the companies' business decisions and sharply focusing their IT investments. Draws on the findings of a multiyear survey to review the different IT assets in which companies invest before discussing the gap in IT investment returns that separates those with IT savvy from those without. Presents five hallmarks of IT savvy and offers a series of practical suggestions for how managers can start to match IT savvy with the IT asset mix.