The RATS Software Forum

Code: Select all

all 13981
open data Threshold.xls
data(format=xls,org=columns) / index TSD TOD TND
*
set Xindex = 100.0*log(index/index{1})
*
* Estimation using MAXIMIZE
* The initial few lines of this set the estimation range, which needs to
* be done explicitly, and the number of variables. Then, vectors for the
* dependent variables, residuals and residuals formulas are set up. The
* SET instructions copy the dependent variables over into the slots in
* the vector of series.
*
compute gstart=2,gend=13981
compute n=4
dec vect[series] y(n) u(n)
dec vect[frml] resid(n)
set y(1) = Xindex
set DUMMY1 = TSD
set DUMMY2 = TOD
set DUMMY3 = TND 
* This is specific to a mean-only model. It sets up the formulas (the &i
* are needed in the formula definitions when the FRML is defined in a
* loop), and estimates them using NLSYSTEM. This both initializes the
* mean parameters, and computes the unconditional covariance matrix. If
* you want more general mean equations, the simplest way to do that
* would be to define each FRML separately.
*
dec vect b(n)
nonlin(parmset=meanparms) b
do i=1,n
   frml resid(i) = (y(&i)-b(&i))
end do i
nlsystem(parmset=meanparms,resids=u) gstart gend resid
compute rr=%sigma
*
* The paths of the covariance matrices and uu' are saved in the
* SERIES[SYMM] names H and UU. UX and HX are used to pull in residuals
* and H matrices.
*
declare series[symm] h uu
*
* ux is used when extracting a u vector
*
declare symm hx(n,n)
declare vect ux(n)
*
* These are used to initialize pre-sample variances.
*
gset h  * gend = rr
gset uu * gend = rr
*
* This is a standard (normal) log likelihood formula for any
* multivariate GARCH model. The difference among these will be in the
* definitions of HF and RESID. The function %XT pulls information out of
* a matrix of SERIES.
*
declare frml[symm] hf
*
frml logl = $
    hx = hf(t) , $
    %do(i,1,n,u(i)=resid(i)) , $
    ux = %xt(u,t), $
    h(t)=hx, uu(t)=%outerxx(ux), $
    %logdensity(hx,ux)
*****************************************************
*
* Panel GARCH - DVECH with restrictions
*
dec symm vcs(n,n)
dec real delta lambda gamma rho
dec symm vbs(n,n) vas(n,n)
*
compute vcs=rr*.1,delta=lambda=.8,gamma=rho=.1
nonlin(parmset=garchparms) vcs delta lambda gamma rho
frml hf = vcs+vbs.*h{1}+vas.*uu{1}
*
* Call once during START option to fill in the VAS and VBS arrays
*
function PGARCHInit
local integer i j
ewise vbs(i,j)=%if(i==j,delta,lambda)
ewise vas(i,j)=%if(i==j,gamma,rho)
end
*
maximize(start=PGARCHInit(),parmset=meanparms+garchparms,pmethod=simplex,piters=10,method=bfgs,iters=400) logl gstart gend