function PC = expectedPC(p)
%PC = expectedPC(p)
%
%expected probability correct for the standard diffusion model
%
%Inputs:
% p.a  upper bound (correct answer)
% p.b  lower bound (incorrect answer)
% p.s  standard deviation of drift (units/sec)
% p.u  drift rate (units/sec)

PC = (exp(2*p.u*p.b/p.s^2)-1)/(exp(2*p.u*p.b/p.s^2)-exp(-2*p.u*p.a/p.s^2));
