In this blog post, librarian Joyce Valenza offers ideas on how to help students judge the credibility of social media sources that lack the more traditional credentials of established journalists and researchers. She suggests four sites where students can obtain metrics of social influence, and gain insight about establishing their own online presence. "While these tools may be useful in exploring the influence and perhaps expertise of others, they also have growing importance in how our students will be measured in the world of business," Valenza writes.