Become an expert in R — Interactive courses, Cheat Sheets, certificates and more!
Get Started for Free

sd.fts

Standard deviation functions for functional time series


Description

Computes standard deviation of functional time series at each variable.

Usage

## S3 method for class 'fts'
sd(x, method = c("coordinate", "FM", "mode", "RP", "RPD", "radius"), 
 trim = 0.25, alpha, weight,...)

Arguments

x

An object of class fts.

method

Method for computing median.

trim

Percentage of trimming.

alpha

Tuning parameter when method="radius".

weight

Hard thresholding or soft thresholding.

...

Other arguments.

Details

If method = "coordinate", it computes coordinate-wise standard deviation functions.

If method = "FM", it computes the standard deviation functions of trimmed functional data ordered by the functional depth of Fraiman and Muniz (2001).

If method = "mode", it computes the standard deviation functions of trimmed functional data ordered by h-modal functional depth.

If method = "RP", it computes the standard deviation functions of trimmed functional data ordered by random projection depth.

If method = "RPD", it computes the standard deviation functions of trimmed functional data ordered by random projection with derivative depth.

If method = "radius", it computes the standard deviation function of trimmed functional data ordered by the notion of alpha-radius.

Value

A list containing x = variables and y = standard deviation rates.

Author(s)

Han Lin Shang

References

O. Hossjer and C. Croux (1995) "Generalized univariate signed rank statistics for testing and estimating a multivariate location parameter", Nonparametric Statistics, 4(3), 293-308.

A. Cuevas and M. Febrero and R. Fraiman (2006) "On the use of bootstrap for estimating functions with functional data", Computational Statistics \& Data Analysis, 51(2), 1063-1074.

A. Cuevas and M. Febrero and R. Fraiman (2007), "Robust estimation and classification for functional data via projection-based depth notions", Computational Statistics, 22(3), 481-496.

M. Febrero and P. Galeano and W. Gonzalez-Manteiga (2007) "A functional analysis of NOx levels: location and scale estimation and outlier detection", Computational Statistics, 22(3), 411-427.

M. Febrero and P. Galeano and W. Gonzalez-Manteiga (2008) "Outlier detection in functional data by depth measures, with application to identify abnormal NOx levels", Environmetrics, 19(4), 331-345.

M. Febrero and P. Galeano and W. Gonzalez-Manteiga (2010) "Measures of influence for the functional linear model with scalar response", Journal of Multivariate Analysis, 101(2), 327-339.

J. A. Cuesta-Albertos and A. Nieto-Reyes (2010) "Functional classification and the random Tukey depth. Practical issues", Combining Soft Computing and Statistical Methods in Data Analysis, Advances in Intelligent and Soft Computing, 77, 123-130.

D. Gervini (2012) "Outlier detection and trimmed estimation in general functional spaces", Statistica Sinica, 22(4), 1639-1660.

See Also

Examples

# Fraiman-Muniz depth was arguably the oldest functional depth.	
sd(x = ElNino_ERSST_region_1and2, method = "FM")
sd(x = ElNino_ERSST_region_1and2, method = "coordinate")
sd(x = ElNino_ERSST_region_1and2, method = "mode")
sd(x = ElNino_ERSST_region_1and2, method = "RP")
sd(x = ElNino_ERSST_region_1and2, method = "RPD")
sd(x = ElNino_ERSST_region_1and2, method = "radius", 
	alpha = 0.5, weight = "hard")
sd(x = ElNino_ERSST_region_1and2, method = "radius", 
	alpha = 0.5, weight = "soft")

ftsa

Functional Time Series Analysis

v6.0
GPL-3
Authors
Rob Hyndman [aut] (<https://orcid.org/0000-0002-2140-5352>), Han Lin Shang [aut, cre, cph] (<https://orcid.org/0000-0003-1769-6430>)
Initial release
2020-11-29

We don't support your browser anymore

Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.