title1 'Simulated ARIMA(1,1,1)'; data a; u1=0; u2=0 ; a1 = 0; do i = -50 to 200; a = 0.2*rannor(1); u = (4.0/3)*u1 - (1.0/3)*u2 + a + (1.0/6)*a1; if i > 0 then output; u2 = u1; u1 = u; a1 = a; end; run;Tester la staionnarité avec l'option
stationarity=(DICKEY)
; Expliquer les resultats.
identify var=u(1) nlag=12 minic scan esacf;run;+