function [] = chap_5_prob_30()
% 
% Written by:
% -- 
% John L. Weatherwax                2007-04-02
% 
% email: wax@alum.mit.edu
% 
% Please send comments and especially bug reports to the
% above email address.
% 
%-----

pegw = 1-normcdf(1/2)
pegb = normcdf(-1/3)
alpha = pegw/(pegw+pegb)