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Causality in Time Series - ClopiNet

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Popescuβ > 0 y C,i =x N,i =⎡K∑︁k=1⎢⎣⎡K∑︁k=1⎢⎣a 11 0 0a 12 a 22 0 y⎤⎥⎦ C,i−k + w C,i (39)0 0 a 33 C,ka 11 0 00 a 22 0 x⎤⎥⎦ N,i−k + w N,i0 0 a 22 N,ky N,i = Bx N,i (40)x D,i =⎡K∑︁k=1⎢⎣a 11 0 a 130 a 22 a 23 x⎤⎥⎦ D,i−k + w D,i0 0 a 22 D,ky MC = (1 − |β|)y N + |β|y C‖y N ‖ F‖y C ‖ F(41)y DC = (1 − χ )y MC + χ y D‖y MC ‖ F‖y D ‖ F(42)The Table 3, similar to the tables <strong>in</strong> the preced<strong>in</strong>g section, shows results for allusual methods, except for PSIpartial which is PSI calculated on the partial coherenceas def<strong>in</strong>ed above and calculated from Welch (cross-spectral) estimators <strong>in</strong> the case ofmixed noise and a common driver.Table 3: TRIPLES: Commonly driven, additive mixed colored noiseMax. Accuracy TP , FP< 0.10100 500 1000 5000 100 500 1000 5000Ψ p 0.53 0.61 0.71 0.75 0.12 0.31 0.49 0.56Ψ 0.54 0.60 0.70 0.72 0.10 0.25 0.40 0.52CSI 0.51 0.60 0.69 0.76 0.09 0.27 0.38 0.45PDC 0.55 0.54 0.60 0.58 0.13 0.12 0.16 0.13DTF 0.51 0.56 0.59 0.61 0.12 0.09 0.09 0.11Notice that the TP rates are lower for all methods with respect to Table 2 whichrepresents the mixed noise situation without any common driver.10. DiscussionIn a recent talk, Emanuel Parzen (Parzen, 2004) proposed, both <strong>in</strong> h<strong>in</strong>dsight and forfuture consideration, that aim of statistics consist <strong>in</strong> an ‘answer mach<strong>in</strong>e’, i.e. a more<strong>in</strong>telligent, automatic and comprehensive version of Fisher’s almanac, which currentlyconsists <strong>in</strong> a plenitude of chapters and sections related to different types of hypotheses62

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