Analyses of Baby Name Popularity Distribution in U.S. for the Last 131   Years
  We examine the complete dataset of baby name popularity collected by U.S. Social Security Administration for the last 131 years (1880-2010). The ranked baby name popularity can be fitted empirically by a piecewise function consisting of Beta function for the high-ranking names and power-law function for low-ranking names, but not power-law (Zipf's law) or Beta function by itself. 
Wentian Li
nlin.AO stat.AP