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Local outlier factors

Source: R/lof_scores.R
lof_scores.Rd

Compute local outlier factors using k nearest neighbours. A local outlier factor is a measure of how anomalous each observation is based on the density of neighbouring points. The function uses dbscan::lof to do the calculation.

Usage

lof_scores(y, k = 10, ...)

Arguments

y

Numerical matrix or vector of data

k

Number of neighbours to include. Default: 5.

...

Additional arguments passed to dbscan::lof

Value

Numerical vector containing LOF values

See also

dbscan::lof

Author

Rob J Hyndman

Examples

y <- c(rnorm(49), 5)
lof_scores(y)
#>  [1] 1.0955266 1.3574208 0.9696143 1.1475907 3.5454478 1.1233799 1.0004632
#>  [8] 0.9643146 1.0277538 3.3031776 1.1992162 0.9866341 5.3386595 0.9715848
#> [15] 1.1045910 1.0021149 0.9524208 0.9809341 0.9731295 0.9665192 1.1985913
#> [22] 1.0082528 0.9727545 0.9818846 1.0261673 1.0450118 1.1541490 1.1614945
#> [29] 1.1836568 0.9938886 1.1619525 1.0490273 0.9886596 0.9806469 1.1797346
#> [36] 2.9499290 1.0032971 0.9789979 0.9821030 2.9462327 1.0340114 0.9996365
#> [43] 1.1322514 1.0005447 1.1764123 3.4474268 1.1951352 1.4531626 1.0213928
#> [50] 8.4933360