function y = lnbernoulike(r,x);
% This is the NEGATIVE of the log likelihood function for X ~ Bernoulli(p)
%--------------------------------------------------------------
% OUTPUT: y = value of the likelihood function given:
% INPUT:  r = Bernoulli parameter for minimization, we'll diff w.r.t. it.
%         parameters
%         x = vector of iid Bernoulli draws
    
%Strangly, we've found that variables of interest need to be included as "r
%subscript 1" which in MatLab is "r(1)". We had to do this even though we
%only have one variable.

m = size(x,1);
xbar = mean(x);

y = -(m*xbar*log(r(1)) + m*(1-xbar)*log(1-r(1)));