supstat/vistat — pull request #2 by yulijia (2013-03-26 00:43:13+00:00)
Title: a new post and some update

1. post a new article 'Gradient Descent Algorithm with R'
2. update _config.yml , add a new author
3. fix a typo in '2012-11-06-brownian-motion-with-r.Rmd'