dynare/matlab/mr_hessian.m

257 lines
8.8 KiB
Matlab

function [hessian_mat, gg, htol1, ihh, hh_mat0, hh1] = mr_hessian(init,x,func,hflag,htol0,DynareDataset,DynareOptions,Model,EstimatedParameters,BayesInfo,DynareResults)
% [hessian_mat, gg, htol1, ihh, hh_mat0, hh1] = mr_hessian(init,x,func,hflag,htol0,varargin)
%
% numerical gradient and Hessian, with 'automatic' check of numerical
% error
%
% adapted from Michel Juillard original rutine hessian.m
%
% func = function handle. The function must give two outputs:
% - the log-likelihood AND the single contributions at times t=1,...,T
% of the log-likelihood to compute outer product gradient
% x = parameter values
% hflag = 0, Hessian computed with outer product gradient, one point
% increments for partial derivatives in gradients
% hflag = 1, 'mixed' Hessian: diagonal elements computed with numerical second order derivatives
% with correlation structure as from outer product gradient;
% two point evaluation of derivatives for partial derivatives
% in gradients
% hflag = 2, full numerical Hessian, computes second order partial derivatives
% uses Abramowitz and Stegun (1965) formulas 25.3.24 and 25.3.27
% p. 884.
% htol0 = 'precision' of increment of function values for numerical
% derivatives
%
% varargin: other parameters of func
% Copyright (C) 2004-2012 Dynare Team
%
% This file is part of Dynare.
%
% Dynare 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 3 of the License, or
% (at your option) any later version.
%
% Dynare 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 Dynare. If not, see <http://www.gnu.org/licenses/>.
persistent h1 htol
n=size(x,1);
if init
gstep_=DynareOptions.gstep;
htol = 1.e-4;
h1=DynareOptions.gradient_epsilon*ones(n,1);
return
end
[f0, ff0]=feval(func,x,DynareDataset,DynareOptions,Model,EstimatedParameters,BayesInfo,DynareResults);
h2=BayesInfo.ub-BayesInfo.lb;
hmax=BayesInfo.ub-x;
hmax=min(hmax,x-BayesInfo.lb);
if isempty(ff0),
outer_product_gradient=0;
else
outer_product_gradient=1;
end
h1 = min(h1,0.5.*hmax);
if htol0<htol
htol=htol0;
end
xh1=x;
f1=zeros(size(f0,1),n);
f_1=f1;
if outer_product_gradient
ff1=zeros(size(ff0));
ff_1=ff1;
ggh=zeros(size(ff0,1),n);
end
i=0;
while i<n
i=i+1;
h10=h1(i);
hcheck=0;
xh1(i)=x(i)+h1(i);
try
[fx, ffx]=feval(func,xh1,DynareDataset,DynareOptions,Model,EstimatedParameters,BayesInfo,DynareResults);
catch
fx=1.e8;
end
it=1;
dx=(fx-f0);
ic=0;
icount = 0;
h0=h1(i);
while (abs(dx(it))<0.5*htol || abs(dx(it))>(3*htol)) && icount<10 && ic==0
icount=icount+1;
if abs(dx(it))<0.5*htol
if abs(dx(it)) ~= 0,
h1(i)=min(max(1.e-10,0.3*abs(x(i))), 0.9*htol/abs(dx(it))*h1(i));
else
h1(i)=2.1*h1(i);
end
h1(i) = min(h1(i),0.5*hmax(i));
xh1(i)=x(i)+h1(i);
try
[fx, ffx]=feval(func,xh1,DynareDataset,DynareOptions,Model,EstimatedParameters,BayesInfo,DynareResults);
catch
fx=1.e8;
end
end
if abs(dx(it))>(3*htol)
h1(i)= htol/abs(dx(it))*h1(i);
xh1(i)=x(i)+h1(i);
try
[fx, ffx]=feval(func,xh1,DynareDataset,DynareOptions,Model,EstimatedParameters,BayesInfo,DynareResults);
catch
fx=1.e8;
end
while (fx-f0)==0
h1(i)= h1(i)*2;
xh1(i)=x(i)+h1(i);
[fx, ffx]=feval(func,xh1,DynareDataset,DynareOptions,Model,EstimatedParameters,BayesInfo,DynareResults);
ic=1;
end
end
it=it+1;
dx(it)=(fx-f0);
h0(it)=h1(i);
if (h1(i)<1.e-12*min(1,h2(i)) && h1(i)<0.5*hmax(i))% || (icount==10 && abs(dx(it))>(3*htol)),
ic=1;
hcheck=1;
end
end
f1(:,i)=fx;
if outer_product_gradient,
if any(isnan(ffx)) || isempty(ffx),
ff1=ones(size(ff0)).*fx/length(ff0);
else
ff1=ffx;
end
end
xh1(i)=x(i)-h1(i);
[fx, ffx]=feval(func,xh1,DynareDataset,DynareOptions,Model,EstimatedParameters,BayesInfo,DynareResults);
f_1(:,i)=fx;
if outer_product_gradient,
if any(isnan(ffx)) || isempty(ffx),
ff_1=ones(size(ff0)).*fx/length(ff0);
else
ff_1=ffx;
end
ggh(:,i)=(ff1-ff_1)./(2.*h1(i));
end
xh1(i)=x(i);
if hcheck && htol<1
htol=min(1,max(min(abs(dx))*2,htol*10));
h1(i)=h10;
i=0;
end
end
h_1=h1;
xh1=x;
xh_1=xh1;
gg=(f1'-f_1')./(2.*h1);
if outer_product_gradient,
if hflag==2
gg=(f1'-f_1')./(2.*h1);
hessian_mat = zeros(size(f0,1),n*n);
for i=1:n
if i > 1
k=[i:n:n*(i-1)];
hessian_mat(:,(i-1)*n+1:(i-1)*n+i-1)=hessian_mat(:,k);
end
hessian_mat(:,(i-1)*n+i)=(f1(:,i)+f_1(:,i)-2*f0)./(h1(i)*h_1(i));
temp=f1+f_1-f0*ones(1,n);
for j=i+1:n
xh1(i)=x(i)+h1(i);
xh1(j)=x(j)+h_1(j);
xh_1(i)=x(i)-h1(i);
xh_1(j)=x(j)-h_1(j);
temp1 = feval(func,xh1,DynareDataset,DynareOptions,Model,EstimatedParameters,BayesInfo,DynareResults);
temp2 = feval(func,xh_1,DynareDataset,DynareOptions,Model,EstimatedParameters,BayesInfo,DynareResults);
hessian_mat(:,(i-1)*n+j)=-(-temp1 -temp2+temp(:,i)+temp(:,j))./(2*h1(i)*h_1(j));
xh1(i)=x(i);
xh1(j)=x(j);
xh_1(i)=x(i);
xh_1(j)=x(j);
j=j+1;
end
i=i+1;
end
elseif hflag==1
hessian_mat = zeros(size(f0,1),n*n);
for i=1:n
dum = (f1(:,i)+f_1(:,i)-2*f0)./(h1(i)*h_1(i));
if dum>eps
hessian_mat(:,(i-1)*n+i)=dum;
else
hessian_mat(:,(i-1)*n+i)=max(eps, gg(i)^2);
end
end
end
gga=ggh.*kron(ones(size(ff1)),2.*h1'); % re-scaled gradient
hh_mat=gga'*gga; % rescaled outer product hessian
hh_mat0=ggh'*ggh; % outer product hessian
A=diag(2.*h1); % rescaling matrix
% igg=inv(hh_mat); % inverted rescaled outer product hessian
ihh=A'*(hh_mat\A); % inverted outer product hessian
if hflag>0 && min(eig(reshape(hessian_mat,n,n)))>0
hh0 = A*reshape(hessian_mat,n,n)*A'; %rescaled second order derivatives
hh = reshape(hessian_mat,n,n); %rescaled second order derivatives
sd0=sqrt(diag(hh0)); %rescaled 'standard errors' using second order derivatives
sd=sqrt(diag(hh_mat)); %rescaled 'standard errors' using outer product
hh_mat=hh_mat./(sd*sd').*(sd0*sd0'); %rescaled inverse outer product with 'true' std's
igg=inv(hh_mat); % rescaled outer product hessian with 'true' std's
ihh=A'*(hh_mat\A); % inverted outer product hessian
hh_mat0=inv(A)'*hh_mat*inv(A); % outer product hessian with 'true' std's
sd=sqrt(diag(ihh)); %standard errors
sdh=sqrt(1./diag(hh)); %diagonal standard errors
for j=1:length(sd)
sd0(j,1)=min(BayesInfo.p2(j), sd(j)); %prior std
sd0(j,1)=10^(0.5*(log10(sd0(j,1))+log10(sdh(j,1))));
end
ihh=ihh./(sd*sd').*(sd0*sd0'); %inverse outer product with modified std's
igg=inv(A)'*ihh*inv(A); % inverted rescaled outer product hessian with modified std's
hh_mat=inv(igg); % outer product rescaled hessian with modified std's
hh_mat0=inv(A)'*hh_mat*inv(A); % outer product hessian with modified std's
% sd0=sqrt(1./diag(hh0)); %rescaled 'standard errors' using second order derivatives
% sd=sqrt(diag(igg)); %rescaled 'standard errors' using outer product
% igg=igg./(sd*sd').*(sd0*sd0'); %rescaled inverse outer product with 'true' std's
% hh_mat=inv(igg); % rescaled outer product hessian with 'true' std's
% ihh=A'*igg*A; % inverted outer product hessian
% hh_mat0=inv(A)'*hh_mat*inv(A); % outer product hessian with 'true' std's
end
if hflag<2
hessian_mat=hh_mat0(:);
end
if any(isnan(hessian_mat))
hh_mat0=eye(length(hh_mat0));
ihh=hh_mat0;
hessian_mat=hh_mat0(:);
end
hh1=h1;
save hess.mat hessian_mat
else
hessian_mat=[];
ihh=[];
hh_mat0 = [];
hh1 = [];
end
htol1=htol;