loop: LoOP Outlier score calculation

Description Usage Arguments Value See Also Examples

View source: R/outlier_lof.R

Description

loop returns the LoOP Outlier score for every observation in the given data_matrix. LoOP is short for Local Outlier Probabilities. LOF in combination with statistical methods is used to calculate outlier score.

Usage

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loop(data_matrix, k_reach, k_comp = k_reach, lambda = NA)

Arguments

data_matrix

numeric Matrix containing data the outlier score is calculated for. Rows are treated as observations, columns as features.

k_reach

Number. Neighbourhood-size used to calculate outlier scores.

k_comp

Number. Neighbourhood-size used to calculate outlier scores. Defaults to k_reach

lambda

Number. If NA, ELKI's default is used (2.0).

Value

List of outlier scores. The score at position x belongs to the observation given in row x of the original data_matrix.

See Also

https://elki-project.github.io/releases/release0.7.5/javadoc/de/lmu/ifi/dbs/elki/algorithm/outlier/lof/LoOP.html for ELKI documentation.

Examples

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data_matrix <- matrix(c(1:30), nrow=10, ncol=3)
result      <- loop(data_matrix, 3)
for(index in c(1:10)) {
    print(paste('Observation:', paste(data_matrix[index,], collapse=',')))
    print(paste('Score:',       result[index]))
}

lenaWitterauf/rElki documentation built on June 2, 2020, 9:24 p.m.