;;
;;  AIRMULT.MAC: macro to analyze airline data
;;
;;  INPUT: none
pause
;start

read(air,x,n)

lx=loge(x)
label(lx)='Log airline data'

dlx=diff(n,1,lx)
n=n-1
label(dlx)='1st difference airline data'
dd12lx=diff(n,12,dlx)
n=n-12
label(dd12lx)='1st, 12th difference airline data'

ploton
batchon
plotsize(1)
plot(x)
plotsize(2)
plot(lx)
plotsize(3)
plot(dlx)
plotsize(4)
batchoff
plot(dd12lx)
plotoff
 
kopt=-3
k1=3
k2=0
alpha=<1,12,13>
y=dd12lx
armasel(y,n,60,20,k1,k2,kopt,.9,p,q,alpha,beta,rvar,ier)
alpha
list({alpha[1]*alpha[12]})