Skip to contents

Identifies bandwidth for outlier detection.

Source: R/bandwidth.R
find_tda_bw.Rd

This function identifies the bandwidth that is used in the kernel density estimate computation. The function uses topological data analysis (TDA) to find the badnwidth.

Usage

find_tda_bw(X, fast = TRUE, gamma = 0.95, use_differences = FALSE)

Arguments

X

The numerical input data in a data.frame, matrix or tibble format.

fast

If TRUE (default), makes the computation faster by sub-setting the data for the bandwidth calculation.

gamma

Parameter for bandwidth calculation giving the quantile of the Rips death radii to use for the bandwidth. Default is 0.97. Ignored under the old version; where the lower limit of the maximum Rips death radii difference is used. Also ignored if bw is provided.

use_differences

If TRUE, the bandwidth is set to the lower point of the maximum Rips death radii differences. If FALSE, the gamma quantile of the Rips death radii is used. Default is FALSE.

Value

The bandwidth

Examples

X <- rbind(
  data.frame(
    x = rnorm(500),
    y = rnorm(500)
  ),
  data.frame(
    x = rnorm(5, mean = 10, sd = 0.2),
    y = rnorm(5, mean = 10, sd = 0.2)
  )
)
find_tda_bw(X, fast = TRUE)
#> [1] 0.9238231