nomclust (version 2.6.2)

good2: Goodall 2 (G2) Measure

Description

The function calculates a dissimilarity matrix based on the G2 similarity measure.

Usage

good2(data, var.weights = NULL)

Value

The function returns an object of the class "dist".

Arguments

data

A data.frame or a matrix with cases in rows and variables in columns.

var.weights

A numeric vector setting weights to the used variables. One can choose the real numbers from zero to one.

Author

Zdenek Sulc.
Contact:

Details

The Goodall 2 similarity measure was presented in (Boriah et al., 2008). It is a simple modification of the original Goodall measure (Goodall, 1966). The measure assigns weight to infrequent matches under the condition that there are also other categories, which are even less frequent than the examined one.

References

Boriah S., Chandola V., Kumar V. (2008). Similarity measures for categorical data: A comparative evaluation. In: Proceedings of the 8th SIAM International Conference on Data Mining, SIAM, p. 243-254.

Goodall V.D. (1966). A new similarity index based on probability. Biometrics, 22(4), p. 882.

See Also

anderberg, burnaby, eskin, gambaryan, good1, goodall1, goodall2, good3, goodall3, good4, goodall4, iof, lin, lin1, of, sm, smirnov, ve, vm.

Examples

# sample data
data(data20)

# dissimilarity matrix calculation
prox.good2 <- good2(data20)

# dissimilarity matrix calculation with variable weights
weights.good2 <- good2(data20, var.weights = c(0.7, 1, 0.9, 0.5, 0))