%
% Written by:
% -- 
% John L. Weatherwax                2008-02-20
% 
% email: wax@alum.mit.edu
% 
% Please send comments and especially bug reports to the
% above email address.
% 
%-----

clear all; 
close all; 
clc; 

addpath('../../Code/CSTool');
load lawpop;      % <- the total population 

for ti=1:2, 
  x = lawpop(:,ti);
  n = length(x); 
  T = median(x);

  % compute the jackknifed replicates of the median statistic:
  jack = zeros(1,n); % <- store the jackknifed replicates
  for ii=1:n
    jack(ii) = median( x( setdiff(1:n,ii) ) ); 
  end

  fprintf('the unique jackknifed replicates are given by\n');
  unique(jack)

  % get the mean of the jackknifed estimates
  TJ = mean(jack);  
  jackBias = (n-1)*(TJ-T);
  jackEstStdError = sqrt( ((n-1)/n)*sum( ( jack - TJ ).^2 ) ); 
  
  % (of the gpa): 
  fprintf('the jackknifed estimate of the SE of the median of component %d is %10.5f\n', ti, jackEstStdError );
  fprintf('the jackknifed estimate of the bias in the median of component %d is %10.5f\n', ti, jackBias );
end