This function constructs the amplitude boxplot.
ampbox_data(warp_median, alpha = 0.05, ka = 1)Returns an ampbox object containing:
median_y: median function
Q1: First quartile
Q3: Second quartile
Q1a: First quantile based on alpha
Q3a: Second quantile based on alpha
minn: minimum extreme function
maxx: maximum extreme function
outlier_index: indexes of outlier functions
fmedian: median function
fdawarp object from time_warping() of aligned data using
the median
quantile value (default=.05, i.e., 95%)
scalar for outlier cutoff (default=1)
Xie, W., S. Kurtek, K. Bharath, and Y. Sun (2016). "A geometric approach to visualization of variability in functional data." Journal of the American Statistical Association in press: 1-34.