transform_lr function

Pairwise Log-Ratios (LR)

Computes all pairwise log-ratio transformation. methods

transform_lr(object, ...)

## S4 method for signature 'CompositionMatrix'
transform_lr(object, weights = FALSE)

## S4 method for signature 'GroupedComposition'
transform_lr(object, weights = FALSE)

Arguments

• object: A CompositionMatrix object.
• ...: Currently not used.
• weights: A logical scalar: should varying weights (column means) be computed? If FALSE (the default), equally-weighted parts are used. Alternatively, a positive numeric vector of weights can be specified (will be rescaled to sum to $1$). Weights will be used internally by other methods (e.g. variance()).

Returns

A LR object.

Examples

## Data from Aitchison 1986
data("hongite")

## Coerce to compositional data
coda <- as_composition(hongite)

## Pairwise log-ratio
lr <- transform_lr(coda)

References

Aitchison, J. (1986). The Statistical Analysis of Compositional Data. London: Chapman and Hall.

Greenacre, M. J. (2019). Compositional Data Analysis in Practice. Boca Raton: CRC Press.

Greenacre, M. J. (2021). Compositional Data Analysis. Annual Review of Statistics and Its Application, 8(1): 271-299. tools:::Rd_expr_doi("10.1146/annurev-statistics-042720-124436") .

See Also

Other log-ratio transformations: transform_alr(), transform_clr(), transform_ilr(), transform_inverse(), transform_plr()

Author(s)

N. Frerebeau