diff --git a/matlab/DiffuseLikelihoodH3.m b/matlab/DiffuseLikelihoodH3.m index 2a6f995ca..11f000320 100644 --- a/matlab/DiffuseLikelihoodH3.m +++ b/matlab/DiffuseLikelihoodH3.m @@ -1,4 +1,35 @@ function [LIK, lik] = DiffuseLikelihoodH3(T,R,Q,H,Pinf,Pstar,Y,trend,start) + +% function [LIK, lik] = DiffuseLikelihoodH3(T,R,Q,H,Pinf,Pstar,Y,trend,start) +% Computes the diffuse likelihood with measurement error, in the case of +% a singular var-cov matrix. +% Univariate treatment of multivariate time series. +% +% INPUTS +% T: mm*mm matrix +% R: mm*rr matrix +% Q: rr*rr matrix +% H: pp*pp matrix +% Pinf: mm*mm diagonal matrix with with q ones and m-q zeros +% Pstar: mm*mm variance-covariance matrix with stationary variables +% Y: pp*1 vector +% trend +% start: likelihood evaluation at 'start' +% +% OUTPUTS +% LIK: likelihood +% lik: density vector in each period +% +% SPECIAL REQUIREMENTS +% See "Filtering and Smoothing of State Vector for Diffuse State Space +% Models", S.J. Koopman and J. Durbin (2003, in Journal of Time Series +% Analysis, vol. 24(1), pp. 85-98). +% +% part of DYNARE, copyright Dynare Team (2005-2008) +% Gnu Public License. + + + % M. Ratto added lik in output [October 2005] % changes by M. Ratto % introduced new global variable id_ for termination of DKF @@ -8,77 +39,7 @@ function [LIK, lik] = DiffuseLikelihoodH3(T,R,Q,H,Pinf,Pstar,Y,trend,start) % new termination for DKF % likelihood terms for Fstar must be cumulated in DKF also when Pinf is non % zero. this bug is fixed. -% -% stephane.adjemian@cepremap.cnrs.fr [07-19-2004] -% -% See "Filtering and Smoothing of State Vector for Diffuse State Space -% Models", S.J. Koopman and J. Durbin (2003, in Journal of Time Series -% Analysis, vol. 24(1), pp. 85-98). -% -% Case where F_{\infty,t} is singular ==> Univariate treatment of multivariate -% time series. -% -% THE PROBLEM: -% -% y_t = Z_t * \alpha_t + \varepsilon_t -% \alpha_{t+1} = T_t * \alpha_t + R_t * \eta_t -% -% with: -% -% \alpha_1 = a + A*\delta + R_0*\eta_0 -% -% m*q matrix A and m*(m-q) matrix R_0 are selection matrices (their -% columns constitue all the columns of the m*m identity matrix) so that -% -% A'*R_0 = 0 and A'*\alpha_1 = \delta -% -% We assume that the vector \delta is distributed as a N(0,\kappa*I_q) -% for a given \kappa > 0. So that the expectation of \alpha_1 is a and -% its variance is P, with -% -% P = \kappa*P_{\infty} + P_{\star} -% -% P_{\infty} = A*A' -% P_{\star} = R_0*Q_0*R_0' -% -% P_{\infty} is a m*m diagonal matrix with q ones and m-q zeros. -% -% -% and where: -% -% y_t is a pp*1 vector -% \alpha_t is a mm*1 vector -% \varepsilon_t is a pp*1 multivariate random variable (iid N(0,H_t)) -% \eta_t is a rr*1 multivariate random variable (iid N(0,Q_t)) -% a_1 is a mm*1 vector -% -% Z_t is a pp*mm matrix -% T_t is a mm*mm matrix -% H_t is a pp*pp matrix -% R_t is a mm*rr matrix -% Q_t is a rr*rr matrix -% P_1 is a mm*mm matrix -% -% -% FILTERING EQUATIONS: -% -% v_t = y_t - Z_t* a_t -% F_t = Z_t * P_t * Z_t' + H_t -% K_t = T_t * P_t * Z_t' * F_t^{-1} -% L_t = T_t - K_t * Z_t -% a_{t+1} = T_t * a_t + K_t * v_t -% P_{t+1} = T_t * P_t * L_t' + R_t*Q_t*R_t' -% -% -% DIFFUSE FILTERING EQUATIONS: -% -% a_{t+1} = T_t*a_t + K_{\ast,t}v_t -% P_{\infty,t+1} = T_t*P_{\infty,t}*T_t' -% P_{\ast,t+1} = T_t*P_{\ast,t}*L_{\ast,t}' + R_t*Q_t*R_t' -% K_{\ast,t} = T_t*P_{\ast,t}*Z_t'*F_{\ast,t}^{-1} -% v_t = y_t - Z_t*a_t -% L_{\ast,t} = T_t - K_{\ast,t}*Z_t -% F_{\ast,t} = Z_t*P_{\ast,t}*Z_t' + H_t + global bayestopt_ options_ mf = bayestopt_.mf;