options crt nodate; name bja 'ARMA(1,1) and MA(1) on Box-Jenkins series A'; ? Box-Jenkins benchmark estimations -- p.239 ? Box, G.E.P, and Jenkins, G. "Time Series Analysis: Forecasting ? and Control (revised edition)," (1976) Holden-Day. ? Notes: ? 1. Box-Jenkins use an "unconditional sum of squares" method which ? is supposed to be roughly equivalent to exact ML. It usually ? does not match exactly, but it's fairly close. ? For this reason, the TSP coefficients are not really a verified ? benchmark. A second independent package which estimates exact ML ? ARIMA models is needed to reproduce these coefficients, to make ? these benchmarks more certain. ? 2. The standard errors computed by TSP use the BFGS Hessian approximation, ? with numeric derivatives. They are not likely to be more accurate ? than 1-2 digits relative to a Hessian computed from analytic second ? derivatives. The grad=c4 option is used to make the numeric ? derivatives as accurate as possible. load; title 'ARMA(1,1) with constant'; ? Box-Jenkins TSP Gauss3.2.35 ? p.239 BJEST ARIMA ? phi1 .92 .908685 .90865841 ? (s.e.) (.04) (.023405) (.04453284) ? theta1 .58 .575841 .57577387 ? (s.e.) (.08) (.081197) (.08675614) ? const. 1.45 1.55832 1.55876992 ? (s.e.) (.399388) ? LogL -50.7451 -50.745092 bjest( const,nar=1,ndiff=0,nma=1,nocumpl,noplot,tol=1e-7,exactml,grad=c4) a; title 'MA(1) -- actually ARIMA(0,1,1)'; ? Box-Jenkins TSP Gauss3.2.35 ? p.239 BJEST ARIMA ? theta1 .70 .699384 .69936608 ? (s.e.) (.05) (.064902) (.05180149) ? LogL -53.5087 -53.508690 bjest(noconst,nar=0,ndiff=1,nma=1,nocumpl,noplot,tol=1e-7,exactml,grad=c4) a; end; noprint; smpl 1,197; read a; ? p.525 17.0 16.6 16.3 16.1 17.1 16.9 16.8 17.4 17.1 17.0 16.7 17.4 17.2 17.4 17.4 17.0 17.3 17.2 17.4 16.8 17.1 17.4 17.4 17.5 17.4 17.6 17.4 17.3 17.0 17.8 17.5 18.1 17.5 17.4 17.4 17.1 17.6 17.7 17.4 17.8 17.6 17.5 16.5 17.8 17.3 17.3 17.1 17.4 16.9 17.3 17.6 16.9 16.7 16.8 16.8 17.2 16.8 17.6 17.2 16.6 17.1 16.9 16.6 18.0 17.2 17.3 17.0 16.9 17.3 16.8 17.3 17.4 17.7 16.8 16.9 17.0 16.9 17.0 16.6 16.7 16.8 16.7 16.4 16.5 16.4 16.6 16.5 16.7 16.4 16.4 16.2 16.4 16.3 16.4 17.0 16.9 17.1 17.1 16.7 16.9 16.5 17.2 16.4 17.0 17.0 16.7 16.2 16.6 16.9 16.5 16.6 16.6 17.0 17.1 17.1 16.7 16.8 16.3 16.6 16.8 16.9 17.1 16.8 17.0 17.2 17.3 17.2 17.3 17.2 17.2 17.5 16.9 16.9 16.9 17.0 16.5 16.7 16.8 16.7 16.7 16.6 16.5 17.0 16.7 16.7 16.9 17.4 17.1 17.0 16.8 17.2 17.2 17.4 17.2 16.9 16.8 17.0 17.4 17.2 17.2 17.1 17.1 17.1 17.4 17.2 16.9 16.9 17.0 16.7 16.9 17.3 17.8 17.8 17.6 17.5 17.0 16.9 17.1 17.2 17.4 17.5 17.9 17.0 17.0 17.0 17.2 17.3 17.4 17.4 17.0 18.0 18.2 17.6 17.8 17.7 17.2 17.4 ;