acidity: Acid-neutralizing capacity

In multimode: Mode Testing and Exploring

Description

This dataset, analyzed by Crawford (1994), contains the Acid-Neutralizing Capacity (ANC) measured in a sample of 155 lakes in North-Central Wisconsin (USA). ANC describes the capability of a lake to absorb acid, where low ANC values may lead to a loss of biological resources.

Usage

data(acidity)

Format

acidity includes an acidity index of lakes in north-central Wisconsin on the log scale, in particular, it is provided the log(ANC+50) as in Crawford (1994).

Details

This is a classic example for determining the number of modes.

Source

Obtained from the Supplementary material of Richardson and Green (1997), available in http://www.stats.bris.ac.uk/~peter/mixdata.

References

Crawford (1994). An application of the Laplace method to finite mixture distributions. Journal of the American Statistical Association, 89, 259–267.

Richardson, S. and Green, P. J. (1997). On Bayesian analysis of mixtures with unknown number of components (with discussion). Journal of the Royal Statistical Society, Series B, 59, 731–792.

Examples

data("acidity")
# Kernel density estimation with two modes and SiZer
locmodes(acidity,mod0=2,display=TRUE,xlab="log(ANC+50)")
sizer(acidity,bws=c(0.1,1),xlab="log(ANC+50)")

multimode documentation built on March 21, 2021, 1:06 a.m.