-1650 
eA ys AREY Tops RELATIVE 
pasate ae HEAVE WAVE 
WAVE Soon 
+ a 
Mepoll nici oe ° WAVE HEIGHT Been lenan 
+ HEAVE 
-1619 
e 1701 A RELATIVE WAVE HEIGHT 
ce © MINIMUM AIC 
+ 
+ 
meee -2250 4-2050 
+ 
AIC % 
e A 
0 + 
+ + 
+ 
ee ae a 
-1900 a2 4 «a 4 @4-2300 4-2100 
Oo A e 
Zz a a A 4 e e @ 
A & 6 ; e e 
NO. OF PARAMETER 
Fig. 7.3. Behavior of AIC for seakeeping data in getting the spectra (b) in Fig. 7.2. 
(From Yamanouchi, et al.4°) 
WHITE NOISE €t 
ea Alam 
fiat 
400 500 600 700 800 900 1,000 
TIME t 
SS 
Fig. 7.4. Simulated AR(2) process X, = 0.5 X,, — 0.7 X,2 + &, 
€; is a white noise N(0,1). 
(From Yamanouchi, et al.52) 
230 
