Dear DCM-experts,

I'm trying to use DCM to model phase-coupling. In the beta band it seems to work. Unfortunately in lower bands I get the error:
"Calculated filter coefficients have poles on or outside the unit circle and will not be stable. Try a higher cutoff frequency or a different type/order of filter."

I changed the filter order from 5 to 4 now I'm able to calculate phase-coupling in the alpha-band when I change it to 3 I'm able to go down to 2Hz.
Do I still get reasonable results by cahnging the filter order?
Should I use the same order for all frequency-bands I'm going to analyse or adapt it to the highest possible filter order per frequency-band?

Thanks!
Johannes

  

SMS schreiben mit WEB.DE FreeMail - einfach, schnell und    kostenguenstig. Jetzt gleich testen! http://f.web.de/?mc=021192