windowdrp: Windowed Recurrence Profile

In crqa: Unidimensional and Multidimensional Methods for Recurrence Quantification Analysis

Windowed Recurrence Profile

Description

A recurrence plot is computed in overlapping windows of a specified size for a number of delays smaller than the size of the window. In every window, the recurrence value for the different delays is calculated. A mean is then taken across the delays to obtain a recurrence value in that particular window.

Usage

windowdrp(ts1, ts2, windowstep, windowsize, lagwidth,
radius, delay, embed, rescale, normalize, mindiagline, minvertline,
tw, whiteline, recpt, side, method, metric, datatype)

Arguments

ts1	First time-series
ts2	Second time-series
windowstep	Interval by which the window is moved.
windowsize	The size of the window
lagwidth	The number of delays to be considered within the window
radius	For numeric time-series, the cutoff distance to accept or reject two-points as recurrent
delay	The delay unit by which the series are lagged.
embed	The number of embedding dimension for phase-reconstruction, i.e., the lag intervals.
rescale	Rescale the distance matrix; if rescale = 0 (do nothing); if rescale = 1 (mean distance of entire matrix); if rescale = 2 (maximum distance of entire matrix). if rescale = 3 (minimum distance of entire matrix). if rescale = 4 (euclidean distance of entire matrix).
normalize	Normalize the time-series; if normalize = 0 (do nothing); if normalize = 1 (Unit interval); if normalize = 2 (z-score).
mindiagline	A minimum diagonal length of recurrent points. Usually set to 2, as it takes a minimum of two points to define any line.
minvertline	A minimum vertical length of recurrent points.
tw	The Theiler window parameter
whiteline	A logical flag to calculate (TRUE) or not (FALSE) empty vertical lines.
recpt	A logical flag indicating whether measures of cross-recurrence are calculated directly from a recurrent plot (TRUE) or not (FALSE).
side	A string indicating whether recurrence measures should be calculated in the 'upper' triangle of the RP 'lower' triangle of the matrix, or 'both'. LOC is automatically excluded for 'upper' and 'lower'.
method	A string to indicate the type of recurrence analysis to peform. There are three options: rqa (autorecurrence); crqa(cross-recurrence); mdcrqa(multidimensional recurrence). Default value is crqa
metric	A string to indicate the type of distance metric used, default is euclidean but see help rdist() to list all other possible metrics.
datatype	a string (continuous or categorical) to indicate whether the nature of the data type

Value

It returns a list of arguments where:

profile	Time-course windowed recurrence profile
maxrec	Maximal recurrence observed along the time-course
maxlag	The point where maximal recurrence is observed

Author(s)

Moreno I. Coco ([e-mail]) and Rick Dale ([e-mail])

References

Boker, S. M., Rotondo, J. L., Xu, M., and King, K. (2002). Windowed cross-correlation and peak picking for the analysis of variability in the association between behavioral time series. Psychological Methods, 7(3), 338.

See Also

drpfromts

Examples

# use the available data
data(crqa) 

listener = eyemovement$listener
narrator = eyemovement$narrator

# NB, the parameters for windowsize and windowstep are large to allow
# faster running time, please set them carefully in your analysis. 

delay = 1; embed = 1; rescale = 1; radius = 0.001;
normalize = 0; mindiagline = 2; minvertline = 2;
tw = 0; whiteline = FALSE; recpt = FALSE; side = "both"
method = 'crqa'; metric = 'euclidean';  
datatype = "continuous"; windowsize =  100; 
lagwidth = 10; windowstep = 200

ans = windowdrp(narrator, listener, windowstep, windowsize, lagwidth, 
                radius, delay, embed, rescale, normalize, 
                mindiagline, minvertline, tw, 
                whiteline, recpt, side, method, metric, 
                datatype)


profile = ans$profile; maxrec = ans$maxrec; maxlag = ans$maxlag

plot(profile, type = 'l')

crqa documentation built on June 22, 2024, 9:17 a.m.