Stocks, reporting, post hoc narratives, and how people follow each other.

The Freakonomics blog at the New York Times has a contemplation of how we really have no idea why stocks go up and down as they do. Alan Greenspan admitted as much to Jon Stewart last year. Don't be too sad. I recommend you and your brain read the Black Swan by Nassim Taleb.

It's the Network, Stupid: Why Everything in Medicine Is Connected

PLoS Medicine gets excited about networks.

From the editorial piece: "One need look no further than Facebook to appreciate the significance and power of social networking. (Even PLoS has its own thriving Facebook community, which you can join [here].) But social networking is about more than just friends reunited; it's a framework for understanding even the most basic of biological processes. Two papers in this month's PLoS Medicine illustrate the insight that network theory brings to basic science, and the valuable interdisciplinarity that social network analysis can inspire."

The spread of obesity and other things through social networks

Nicholas Christakis gives his view of health and social networks on
the Edge. Christakis is a professor of sociology and medical sociology
at Harvard and recently carried out some highly publicized work on
the spread of obesity through social networks.