*
* Example 4.4.1 from pp 133-134
*
open data sunspots.dat
cal 1770
data 1770:1 1869:1 spots
boxjenk(ar=2,demean,maxl,method=init,define=ar2) spots
@armaspectrum(footer="Figure 4-14. Spectral Density of Sunspot Data") ar2