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Calculate a stability metric from the multivariate s-map estimated Jacobian

Usage

multiJI(data, winsize = 50, theta_seq = NULL, scale = TRUE)

Source

Ushio, M., Hsieh, Ch., Masuda, R. et al. (2018) Fluctuating interaction network and time-varying stability of a natural fish community. Nature 554, 360–363.

Arguments

data

Numeric matrix with time in first column and species abundances in other columns

winsize

Numeric. Defines the window size of the rolling window as a percentage of the time series length.

theta_seq

Numeric vector of thetas (nonlinear tuning parameters) to estimate the Jacobian over. If `NULL`, a default sequence covering `0:8` is provided.

scale

Boolean. Should data be scaled within each window prior to estimating the Jacobian.

Value

A dataframe where the first column is last time index of the window and the second column is the estimated index value. A value <1.0 indicates stability, a value >1.0 indicates instability.

Examples

#Load the multivariate simulated
#dataset `simTransComms`

data(simTransComms)

#Subset the third community prior to the transition

pre_simTransComms <- subset(simTransComms$community3,time < inflection_pt)

#Estimate the stability index for the third community
#(trimmed for speed)

egJI <- multiJI(data = pre_simTransComms[1:10,2:5],
winsize = 75)