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+// Illustration of nonuniqueness in estimation of MA model parameters using ACF, discussed in Example 6.14 on page 184
+// 6.7
+
+exec('plotacf.sci',-1);
+exec('pacf.sci',-1);
+exec('label.sci',-1);
+
+xi = 0.1*rand(1,10000);
+
+// Simulation and estimation of first model
+m1 = armac(1,0,[1,-3,1.25],1,1,1);
+v1 = arsimul(m1,xi);
+M1 = armax1(0,0,2,v1,zeros(1,10000))
+disp(M1)
+
+// Simulation and estimation of second model
+m2 = armac(1,0,[1,-0.9,0.2],1,1,1);
+v2 = arsimul(m2,xi);
+M2 = armax1(0,0,2,v2,zeros(1,10000))
+disp(M2)
+
+// ACF and PACF of both models
+plotacf(v1,1,11,1); 
+xset('window',1), plotacf(v2,1,11,1);
+xset('window',2), pacf(v1,11);
+xset('window',3), pacf(v2,11);
+