Math is beautiful, enjoy it!

I had M.S. in Financial Engineering at Columbia University, and work at Bloomberg L.P. I am a CFA Charter Holder. Two useful links: MathJax, Real Analysis By Richard F. Bass

List some of my answers for questions I found interesting:

• Proof of Extended Radon-Nikodym Theorem
• Derivative and Anti-derivative
• Expectation of Conditional Random Variables
• Condition on sigma algebra
• Riemann rearrangement theorem at higher dimension
• Intuition for sigma algebra of probability space
• Basis in Hilbert space
• Hamel Basis v.s. Schauder Basis
• Subbasis for Cartesian Product Topology
• SDE for Geometric Brownian Motion

I love Chinese literature and history, and I am a regular swimmer. I could be reached by zhayujie(at)hotmail(dot)com