Everything about quantification of recurrence plots.

Hi everyone,
I have studied about postural fluctuations during quiet stance and I need to establish the radius for the RQA analysis. I read that it can be used 10% of the mean distance between data points in the reconstructed space. What is difficult to me is to calculate this mean. What is the best form?
Thank you,
Paula Arantes
paulamma
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Joined: Tue Jul 14, 2009 00:37

### Re: RQA and radius calculation

Hi Paula,

you can use the CRP toolbox for Matlab. There is the function pss which calculates the mean and maximal phase space diameter (depending on the embedding parameters). You can also normalise your data to standard deviation 1 and then use the threshold as a fraction of the standard deviation. I would like to suggest reading the following paper:

S. Schinkel, O. Dimigen, N. Marwan: Selection of recurrence threshold for signal detection, European Physical Journal – Special Topics, 164(1), 45–53 (2008). http://www.recurrence-plot.tk/bibliogra ... hinkel2008

Best regards
Norbert

Norbert
Expert

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Joined: Wed Jan 4, 2006 11:03
Location: Potsdam Institute for Climate Impact Research, Germany

### Re: RQA and radius calculation

Prof,

Does CRP toolbox computes the measures for time series with many samples?

Thanks
Vinícius Jefferson Dias Vieira, M.Sc.
Electrical Engineering Department,
Federal University of Campina Grande, Brazil
viniciusjdv
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### Re: RQA and radius calculation

Hi,

waht do you mean with many samples? If you ask for the maximal length of time series which can be used in CRP toolbox, just read the FAQ:
http://tocsy.pik-potsdam.de/CRPtoolbox/ ... tml#length

Norbert
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Joined: Wed Jan 4, 2006 11:03
Location: Potsdam Institute for Climate Impact Research, Germany

### Re: RQA and radius calculation

your other question about the clusters is not really clear to me. are you asking to just remove the main diagonal.
honey
honey
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### Re: RQA and radius calculation

Hi
can any one tell me how will i get back my signal again from the recurrence plot?
vramori.mitra
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Joined: Sun Jun 16, 2013 18:22