--- a
+++ b/gmm_example.m
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+# Copyright (C) 2003,2004  Michael Creel michael.creel@uab.es
+# under the terms of the GNU General Public License.
+# 
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ 
+# Copyright (C) 2003  Michael Creel michael.creel@uab.es
+# under the terms of the GNU General Public License.
+# The GPL license is in the file COPYING
+# 
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ 
+# Copyright (C) 2003  Michael Creel michael.creel@uab.es
+# under the terms of the GNU General Public License.
+# The GPL license is in the file COPYING
+# 
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# GMM example file, shows initial consistent estimator,
+# estimation of efficient weight, and second round
+# efficient estimator 
+
+# This also shows how do use data scaling - WHICH YOU SHOULD DO!
+1;
+
+
+# the form a user-written moment function should take
+function m = mymoments(theta, data, momentargs)
+	k = momentargs{1}; # use this so that data can hold dep, indeps, and instr
+	y = data(:,1);
+	x = data(:,2:k+1);
+	w = data(:, k+2:columns(data));
+	lambda = exp(x*theta);
+	e = y ./ lambda - 1;
+	m = dmult(e, w);
+endfunction	
+
+n = 1000;
+k = 5;
+
+x = [ones(n,1) rand(n,k-1)];
+w = [x, rand(n,1)];
+theta = ones(k,1);
+lambda = exp(x*theta);
+y = randp(lambda);
+[xs, scalecoef] = scale_data(x);
+
+
+# The arguments for gmm_estimate
+theta = zeros(k,1);
+data = [y xs w];
+weight = eye(columns(w));
+moments = "mymoments";
+momentargs = {k}; # needed to know where x ends and w starts
+
+# additional args for gmm_results
+names = str2mat("theta1", "theta2", "theta3", "theta4", "theta5");
+title = "Poisson GMM trial";
+control = {100,0,1,1};
+
+
+# initial consistent estimate: only used to get efficient weight matrix, no screen output
+[theta, obj_value, convergence] = gmm_estimate(theta, data, weight, moments, momentargs);
+
+# efficient weight matrix
+# this method is valid when moments are not autocorrelated
+# the user is reponsible to properly estimate the efficient weight
+m = feval(moments, theta, data, momentargs);
+weight = inverse(cov(m));
+
+# second round efficient estimator
+gmm_results(theta, data, weight, moments, momentargs, names, title, scalecoef, control);
+