176 
Fishery Bulletin 109(2) 
Yt 
v] y« 
v yt 
v 12 
vX 2 y, 
Lag 
Lag 
Lag 
Lag 
y t 
v 1 y» 
v 12 y, 
v;v; 2 y. 
Lag Lag Lag Lag 
Figure 2 
Sample autocorrelation function (ACF) and partial autocorrelation function (PACF) of the transformed meagre ( Argyro - 
somus regius) landings. ACF/PACF plots for log 10 -transformed mean-centered data ( y t , far left), lag-1 differenced series 
(Vjy f ), lag-12 differenced series (Vi^), and lag-1 and lag-12 differenced series ( v i V i 2 3V> far right) are displayed. Horizontal 
dashed lines represent the 95% confidence limits valid under the null hypothesis of white noise error structure. 
where y t - the mean-centered log-transformed meagre 
series (i.e., y ? =log 10 x,-4.022) and the values 
in { ) are the standard errors of the estimates. 
Diagnostic checks indicated that the SARIMA model 
was stationary and invertible and did not have redun- 
dant parameters. The residuals were white noise 
(Ljung-Box Q = 3.35, P-value>0.05) and passed asymp- 
totic normality tests (Shapiro-Wilk W=0.97, P-value 
>0.05; Jarque-Bera LM= 4.91, P-value >0.05) indicating 
the model fitted the data and errors were normally 
distributed. The model explained 78.2% of the variance 
of the series. 
The final process equation selected for the meagre 
data was 
log 10 X,= 0.351og 10 A^ 12 +0.651og 10 A ? _ 24 +Z,+0.63Z,_ 1 
+0.56Z ( ._2+ 0.51Z t _ 3 +0.93Z,_ 4 +0.60Z f _ 5 , 
where Z f ~ N (0, 0.025). 
