The 16-year-old Chinese swimmer Ye Shiwen swam more than 5 seconds faster than her personal best in women's 400m individual medley in London 2012 Olympics, winning her a gold. Her performance received high exposure to media and mixed comments, even some controversy. For example, Nature published a news report titled "Why great Olympic feats raise suspicions -- 'Performance profiling' could help to dispel doubts" and immediately raised great attention and a great number of reader comments.
As an effort for myself to better understand the issue and an exercise, I attempted a 'performance profiling' as what the Nature news report's subtitle says. What I did is to analyze the short-term performance increase (or decrease) of top swimmers in 400m IM worldwide during 2011 and 2012, and try to see how Ye Shiwen compares to other good performance improvers. I found there are more than 20 swimmers who are arguably better performance improvers than Ye. What's also worth noting is that Ye is at a particularly interesting spot that her performance is between the majority male and majority female swimmers. Probably not exactly a surprise given she's world's No. 1 in the event. See my summary: http://bit.ly/swimdata. But I wonder if some of the critical eyes here can "cross validate" this approach. What kind of factors should be examined in this kind of "performance profiling" for sports, and specifically for the Ye case?