R: Uncertainty Coefficient

UncertCoef {DescTools} | R Documentation

## Uncertainty Coefficient

### Description

The uncertainty coefficient U(C|R) measures the proportion of uncertainty (entropy) in the column variable Y that is explained by the row variable X. The function has interfaces for a table, a matrix, a data.frame and for single vectors.

### Usage

    UncertCoef(x, y = NULL, direction = c("symmetric", "row", "column"),
               conf.level = NA, p.zero.correction = 1/sum(x)^2, ...)

### Arguments

`x` | a numeric vector, a factor, matrix or data frame.
`y` | `NULL` (default) or a vector, an ordered factor, matrix or data frame with compatible dimensions to x.
`direction` | direction of the calculation. Can be `"row"` (default) or `"column"`, where `"row"` calculates UncertCoef (R|C) ("column dependent").
`conf.level` | confidence level of the interval. If set to `NA` (which is the default) no confidence interval will be calculated.
`p.zero.correction` | slightly nudge zero values so that their logarithm can be calculated
`...` | further arguments are passed to the function `table`, allowing i.e. to set useNA. This refers only to the vector interface.

### Details

The uncertainty coefficient is computed as

U(C|R) = \frac{H(X) + H(Y) - H(XY)}{H(Y)}

and ranges from [0, 1].

### Value

Either a single numeric value, if no confidence interval is required,
or a vector with 3 elements for estimate, lower and upper confidence intervall.

### Author(s)

Andri Signorell <andri@signorell.net> strongly based on code from Antti Arppe <antti.arppe@helsinki.fi>

### References

Theil, H. (1972), Statistical Decomposition Analysis, Amsterdam: North-Holland Publishing Company.

### See Also

`Entropy`, `Lambda`, `Assocs`

### Examples

    # example from Goodman Kruskal (1954)

    m <- as.table(cbind(c(1768,946,115), c(807,1387,438), c(189,746,288), c(47,53,16)))
    dimnames(m) <- list(paste("A", 1:3), paste("B", 1:4))
    m

    # direction default is "symmetric"
    UncertCoef(m)
    UncertCoef(m, conf.level=0.95)

    UncertCoef(m, direction="row")
    UncertCoef(m, direction="column")

[Package DescTools version 0.99.34 Index]