FD.theorcontours {FlexDir}

Contour Lines of a Flexible Dirichlet

Description

Contour lines of a Flexible Dirichlet with given parameters on the ternary diagram or on the right triangle.

Usage

FD.theorcontours(a, p, t, type = "ternary", var = c(1, 2), zoomed = T,
  showgrid = T, nlevels = 10)

Arguments

a

vector of the non-negative alpha parameters.

p

vector of the clusters' probabilities. It must sum to one.

t

non-negative scalar tau parameter.

type

string indicating whether to plot the contour lines on a ternary diagram 'ternary', or on a right triangle plot 'right'.

var

numeric vector containing the two variables to be plotted on the axis. Used only if type='right'.

zoomed

if TRUE, shows only the area where most of the density is concentrated. If FALSE, shows the whole area.

showgrid

if TRUE, shows the axis and the labels. If FALSE, only the graph is printed.

nlevels

approximate number of contour lines to be drawn.

Details

The number of variables in the Flexible Dirichlet must be 3 to draw a plot. Vectors a and p must be of the same length.

References

Ongaro, A. and Migliorati, S. (2013) A generalization of the Dirichlet distribution. Journal of Multivariate Analysis, 114, 412–426.

Migliorati, S., Ongaro, A. and Monti, G. S. (2016) A structured Dirichlet mixture model for compositional data: inferential and applicative issues. Statistics and Computing, doi:10.1007/s11222-016-9665-y.

See Also

FD.generate, FD.density

Examples

alpha <- c(12,7,15)
prob <- c(0.3,0.4,0.3)
tau <- 8
FD.theorcontours(alpha,prob,tau)
FD.theorcontours(alpha,prob,tau, type='right', var=c(3,2), zoomed=FALSE, showgrid=TRUE, nlevels=3)