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+ | ===== FT_CONNECTIVITY_PDC ===== | ||
+ | |||
+ | Note that this reference documentation is identical to the help that is displayed in MATLAB when you type "help ft_connectivity_pdc". | ||
+ | |||
+ | <html><pre> | ||
+ | <a href=/reference/ft_connectivity_pdc><font color=green>FT_CONNECTIVITY_PDC</font></a> computes partial directed coherence. This function implements | ||
+ | the metrices described in Baccala et al., Biological Cybernetics 2001, 84(6), | ||
+ | 463-74. and in Baccala et al., 15th Int.Conf.on DSP 2007, 163-66. | ||
+ | |||
+ | The implemented algorithm has been tested against the implementation in the | ||
+ | SIFT-toolbox. It yields numerically identical results to what is known there as | ||
+ | 'nPDC' (for PDC) and 'GPDC' for generalized pdc. | ||
+ | |||
+ | Use as | ||
+ | [p, v, n] = ft_connectivity_pdc(h, key1, value1, ...) | ||
+ | |||
+ | The input argument H should be a spectral transfer matrix organized as | ||
+ | Nrpt x Nchan x Nchan x Nfreq (x Ntime), | ||
+ | where Nrpt can be 1. | ||
+ | |||
+ | Additional optional input arguments come as key-value pairs: | ||
+ | 'hasjack' = 0 (default) is a boolean specifying whether the input | ||
+ | contains leave-one-outs, required for correct variance | ||
+ | estimate | ||
+ | 'feedback' = string, determining verbosity (default = 'none'), see <a href=/reference/ft_progress><font color=green>FT_PROGRESS</font></a> | ||
+ | 'invfun' = 'inv' (default) or 'pinv', the function used to invert the | ||
+ | transfer matrix to obtain the fourier transform of the | ||
+ | MVAR coefficients. Use 'pinv' if the data are | ||
+ | poorly-conditioned. | ||
+ | 'noisecov' = matrix containing the covariance of the residuals of the | ||
+ | MVAR model. If this matrix is defined, the function | ||
+ | returns the generalized partial directed coherence. | ||
+ | |||
+ | Output arguments: | ||
+ | p = partial directed coherence matrix Nchan x Nchan x Nfreq (x Ntime). | ||
+ | If multiple observations in the input, the average is returned. | ||
+ | v = variance of p across observations. | ||
+ | n = number of observations. | ||
+ | |||
+ | Typically, nrpt should be 1 (where the spectral transfer matrix is | ||
+ | computed across observations. When nrpt>1 and hasjack is true the input | ||
+ | is assumed to contain the leave-one-out estimates of H, thus a more | ||
+ | reliable estimate of the relevant quantities. | ||
+ | |||
+ | See also <a href=/reference/ft_connectivityanalysis><font color=green>FT_CONNECTIVITYANALYSIS</font></a> | ||
+ | </pre></html> | ||