Characterization of Order Statistics in Two Runs Using Conditional   Expectation
  The runs test is a well-known test that is used for checking independence between elements of a sample data sequence. Some of runs tests are based on the longest run and others based on the total runs. In this paper, we consider order statistics of two runs statistics, and obtain their probability mass functions. In addition, the means and variances of the order statistics are derived using traditional conditional expectation. 
Mohammad Reza Kazemi and Ali Akbar Jafari
stat.ME