function ylevf = recmf(y,nlag,w,freq,nfor,begf,sig,tau,theta,r); % PURPOSE: Estimates a Bayesian error correction model of order n % using Random-Walk averaging prior and produces f-step-ahead forecasts. %--------------------------------------------------- % USAGE: yfor = recmf(y,nlag,w,freq,nfor,begf,sig,tau,theta,r) % where: y = an (nobs x neqs) matrix of y-vectors in levels % nlag = the lag length % w = a weighting for important variables % freq = 1 for annual, 4 for quarterly, 12 for monthly % sig = prior variance hyperparameter (see below) % tau = prior variance hyperparameter (see below) % theta = prior variance hyperparameter (see below) % r = # of co-integrating relations to use % (optional: this will be determined using % Johansen's trace test at 95%-level if left blank) % nfor = the forecast horizon % begf = the beginning date of the forecast % priors for important variables are: N(1/ci,sig) for 1st own lag % (ci = # of important) % N( 0 ,tau*sig/k) for lag k=2,...,nlag % priors for unimportant variables are: N( 0 ,theta*sig/k) for lag k % typical values would be: sig = .1-.3, tau = 4-8, theta = .5-1 %--------------------------------------------------- % NOTES: - estimation is carried out in annualized growth terms % hence the need for a freq argument input. % the prior means rely on common (growth-rate) scaling of variables % - constant term included automatically % - x-matrix of exogenous variables not allowed % - error correction variables are automatically % constructed using output from Johansen's ML-estimator %--------------------------------------------------- % RETURNS: % yfor = (nfor x neqs) matrix of levels forecasts for each equation %--------------------------------------------------- % References: LeSage and Krivelyova (1998) % ``A Spatial Prior for Bayesian Vector Autoregressive Models'', % forthcoming Journal of Regional Science, (on http://www.econ.utoledo.edu) % and % LeSage and Krivelova (1997) (on http://www.econ.utoledo.edu) % ``A Random Walk Averaging Prior for Bayesian Vector Autoregressive Models'' % written by: % James P. LeSage, Dept of Economics % University of Toledo % 2801 W. Bancroft St, % Toledo, OH 43606 % jpl@jpl.econ.utoledo.edu [nobs neqs] = size(y); nx = 0; % adjust nobs to feed the lags nmin = min(nobs,begf-1); nobse = nmin - nlag; if nargin == 10 % user supplied r-value % use johansen to determine ec variables % decrement r by 1 when calling johansen jres = johansen(y(1:nmin,:),0,nlag); % recover error correction vectors ecvectors = jres.evec; index = jres.ind; % construct r-error correction variables x = mlag(y(1:nmin,index),1)*ecvectors(:,1:r); [nobs2 nx] = size(x); elseif nargin == 9 % we have to determine r-value jres = johansen(y(1:nmin,:),0,nlag); % find r = # significant co-integrating relations using % the trace statistic output trstat = jres.lr1; tsignf = jres.cvt; r = 0; for i=1:neqs; if trstat(i,1) > tsignf(i,2) r = i; end; end; % recover error correction vectors ecvectors = jres.evec; index = jres.ind; % construct r error correction variables x = mlag(y(1:nmin,index),1)*ecvectors(:,1:r); [nobs2 nx] = size(x); else error('Wrong # of input arguments to recmf'); end; % adjust nvar for constant term and error correction terms k = neqs*nlag+nx+1; % call rvarb to get parameter estimates if nx ~= 0 bmat = rvarb(y(1:begf-1,:),nlag,w,freq,sig,tau,theta,x(1:begf-1,:)); else bmat = rvarb(y(1:begf-1,:),nlag,w,freq,sig,tau,theta); end; yfor = zeros(nfor,neqs); ylev = zeros(nfor,neqs); % given bmat values generate future % growth rate forecasts dy = growthr(y,freq); ylevf = zeros(nfor,neqs); % storage for level forecasts % 1-step-ahead forecast xtrunc = [dy(nmin-(nlag):nmin,:) zeros(1,neqs)]; xfor = mlag(xtrunc,nlag); [xend junk] = size(xfor); xobs = xfor(xend,:); if nx > 0 ecterm = y(begf-1,index)*ecvectors(:,1:r); % add ec variables xvec = [xobs ecterm 1]; else xvec = [xobs 1]; end; % loop over equations for i=1:neqs; bhat = bmat(:,i); yfor(1,i) = xvec*bhat/100; % growth rate forecast ylevf(1,i) = (1+yfor(1,i))*y(begf-freq,i); % construct level forecasts end; xnew = zeros(nlag+1,neqs); % 2 through nlag-step-ahead forecasts for step=2:nlag; if step <= nfor xnew(1:nlag-step+1,:) = dy(nmin-nlag+step:nmin,:); xnew(nlag-step+2:nlag,:) = yfor(1:step-1,:); xnew(nlag+1,:) = zeros(1,neqs); xfor = mlag(xnew,nlag); [xend junk] = size(xfor); xobs = xfor(xend,:); if nx > 0 % add ec variables based on past level forecasts ecterm = ylevf(step-1,index)*ecvectors(:,1:r); xvec = [xobs ecterm 1]; else xvec = [xobs 1]; end; % loop over equations for i=1:neqs; bhat = bmat(:,i); yfor(step,i) = xvec*bhat/100; if freq < step, % here we can use past level forecasts ylevf(step,:) = (1 + yfor(step,:)).*ylevf(step-freq,:); else % case of freq > step, use past actual levels ylevf(step,:) = (1 + yfor(step,:)).*y(begf+step-freq-1,:); end; % end of if freq <= step end; end; end; % nlag through nfore-step-ahead forecasts for step=nlag:nfor-1; if step <= nfor; cnt = step-(nlag-1); for i=1:nlag; xnew(i,:) = yfor(cnt,:); cnt = cnt+1; end; xfor = mlag(xnew,nlag); [xend junk] = size(xfor); xobs = xfor(xend,:); if nx > 0 % add ec variables based on past level forecasts ecterm = ylevf(step,index)*ecvectors(:,1:r); xvec = [xobs ecterm 1]; else xvec = [xobs 1]; end; % loop over equations for i=1:neqs; bhat = bmat(:,i); yfor(step+1,i) = xvec*bhat/100; if freq < step+1, % here we can use past level forecasts ylevf(step+1,:) = (1 + yfor(step+1,:)).*ylevf(step+1-freq,:); else % case of freq > step, use past actual levels ylevf(step+1,:) = (1 + yfor(step+1,:)).*y(begf+step-freq,:); end; % end of if freq <= step end; end; % end of if step end;