% PURPOSE: demo of spacf() % sample partial autocorrelation function estimates % %--------------------------------------------------- % USAGE: spacf_d %--------------------------------------------------- nobs = 110; % generate arma(2,1) model data e = randn(nobs,1); y = zeros(nobs,1); for i=3:nobs; y(i,1) = 10 + 0.8*y(i-1,1) -0.4*y(i-2,1) + e(i,1) + 0.25*e(i-1,1); end; yt = y(11:nobs,1); m = 30; acf = sacf(y,m); pause; pacf = spacf(y,m); pause; tt=1:m; ttp = tt'; fprintf(1,'Lag acf pacf \n'); for i=1:m fprintf(1,'%2d %10.4f %10.4f \n',ttp(i,1),acf(i,1),pacf(i,1)); end;