Since from school days, I have grown enormous interests in behavioral finance. To me, it is the most fascinating branch of all finance theories, as it studies the one market factor that is most powerful and unreliable: the human psychology. Sometimes, you ventured an investment idea or you learned it from some guru, but could not be sure. So you study, check around and found out that not only one guru, two gurus, but three gurus all hold the similar idea and some have taken actions already! Well, it can not be wrong. Great minds think alike. We must make money together. So you become a guru too and inspires more to jump into the river. This is herding behavior. We are more courageous when we are in a group. but group think can be vital. Think of lemmings, the cute little animal that follow one another to jump into the oceans. Do hundreds ......