x16 {ppclust}

Synthetic data set of two variables forming two clusters

Description

A synthetic data set described by Yang & Wu (2006). It consists of two continous variables forming two well-separated clusters in addition to two noise points.

Usage

data(x16)

Format

A data frame with 16 rows and 2 numeric variables:

p1

a numeric variable ranging from 50 to 150

p2

a numeric variable ranging from 145 to 200

cl

a numeric variable ranging from 1 to 4

Note

The data set x16 is recommended to test the performances of the possibilistic and noise clustering algorithms.

References

Yang, M. S. & Wu, K. L. (2006). Unsupervised possibilistic clustering. Pattern Recognition, 39(1): 5-21. <doi:10.1016/j.patcog.2005.07.005>

Examples

data(x16)
x <- x16[,-3]
# descriptive statistics of the variables
summary(x)
# scatter plots for the variable pairs
pairs(x, col=x16$cl, pch=20, cex=2)