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 — reference:ft_connectivity_psi [2018/08/23 14:43] (current) Line 1: Line 1: + =====  FT_CONNECTIVITY_PSI ===== + + Note that this reference documentation is identical to the help that is displayed in MATLAB when you type "help ft_connectivity_psi"​. + + <​html><​pre>​ + <​font color=green>​FT_CONNECTIVITY_PSI​ computes the phase slope index from a data-matrix + containing the cross-spectral density. It implements the method described + in: Nolte et al., Robustly estimating the flow direction of information + in complex physical systems. Physical Review Letters, 2008; 100; 234101. + + Use as + [c, v, n] = ft_connectivity_psi(input,​ ...) + + The input data input should be organized as + Repetitions x Channel x Channel (x Frequency) (x Time) + or + Repetitions x Channelcombination (x Frequency) (x Time) + + The first dimension should be singleton if the input already contains an + average. + + Additional optional input arguments come as key-value pairs: + nbin = scalar,​ half-bandwidth parameter: the number of frequency bins + ​ across which to integrate + hasjack = 0 or 1, specifying whether the repetitions represent + leave-one-out samples (allowing for a variance estimate) + feedback = '​none',​ '​text',​ '​textbar'​ type of feedback showing progress of + computation + dimord = string, specifying how the input matrix should be interpreted + powindx ​  = + normalize = + + The output p contains the phase slope index, v is a variance estimate + which only can be computed if the data contains leave-one-out samples, + and n is the number of repetitions in the input data. If the phase slope + index is positive, then the first chan (1st dim) becomes more lagged (or + less leading) with higher frequency, indicating that it is causally + driven by the second channel (2nd dim) + + See also <​font color=green>​FT_CONNECTIVITYANALYSIS​ +