Stan is a small console application that works on all Unix systems. It is
able to generate several statisical information of a stream. A stream can
be either standard input or given files. Stan can be used in order to analyse
encrypted data or to measure the quality of a pseudo random number generator. 

There are three types of statistics generated by Stan: 

   - General Statistics
     General statistical standard values are based on the bytes of the input
     stream. Stan is able to calculate the mean, the median, the deviation
     and the chi-squared value of the given stream. 

   - Pattern Statistics
     It is possible to do pattern analysis up to a specified pattern length.
     Stan will analyse the patterns inside the stream and output the most
     used patterns and the range of patterns used. 

   - Bit Statistics
     By analysing the bit of the given stream and dividing them into run,
     sequences of the same bit, stan is able to show information that are
     useful for analysing pseudo random numbers. Stan calculates ratios
     between run lengths and 0 runs to 1 runs. 

WWW: http://www.r0q.cx/stan/