hdr                  package:hdrcde                  R Documentation

_H_i_g_h_e_s_t _D_e_n_s_i_t_y _R_e_g_i_o_n_s

_D_e_s_c_r_i_p_t_i_o_n:

     Calculates and plots highest density regions in one dimension
     including the HDR boxplot.

_U_s_a_g_e:

     hdr(x, prob = c(50, 95, 99), den, h, nn=5000, all.modes=FALSE)
     hdr.den(x, prob = c(50, 95, 99), den, h, xlab=NULL, ylab="Density", ...)
     hdr.boxplot(x, prob = c(99, 50), h, boxlabels = "", col = gray((9:1)/10), 
         main="", xlab="", ylab="", pch=1, ...)

_A_r_g_u_m_e_n_t_s:

       x: Numeric vector containing data. In 'hdr' and 'hdr.den', if
          'x' is missing then 'den' must be provided, and the HDR is
          computed from the given density. For 'hdr.boxplot', 'x' can
          be a list containing several vectors.

    prob: Probability coverage required for HDRs

     den: Density of data as list with components 'x' and 'y'. If
          omitted, the density is estimated from 'x' using 'density'.

       h: Optional bandwidth for calculation of density.

      nn: Number of random numbers used in computing f-alpha quantiles.

all.modes: Return all local modes or just the global mode?

boxlabels: Label for each box plotted.

     col: Colours for regions of each box.

    main: Overall title for the plot.

    xlab: Label for x-axis.

    ylab: Label for y-axis.

     pch: Plotting character.

     ...: Other arguments passed to plot.

_D_e_t_a_i_l_s:

     Either 'x' or 'den' must be provided. Hyndman's (1996) density
     quantile algorithm is used for calculation. 'hdr.den' plots the
     density with the HDRs superimposed. 'hdr.boxplot' displays a
     boxplot based on HDRs.

_V_a_l_u_e:

     'hdr.boxplot' retuns nothing. 'hdr' and 'hdr.den' return a list of
     three components: 

     hdr: The endpoints of each interval in each HDR

    mode: The estimated mode of the density.

  falpha: The value of the density at the boundaries of each HDR.

_A_u_t_h_o_r(_s):

     Rob Hyndman

_R_e_f_e_r_e_n_c_e_s:

     Hyndman, R.J. (1996) Computing and graphing highest density
     regions _American Statistician_, *50*, 120-126.

_S_e_e _A_l_s_o:

     'hdr.boxplot.2d'

_E_x_a_m_p_l_e_s:

     hdr(faithful$eruptions)
     hdr.boxplot(faithful$eruptions)
     hdr.den(faithful$eruptions)

     x <- c(rnorm(100,0,1), rnorm(100,3,1))
     par(mfrow=c(1,2))
     boxplot(x)
     hdr.boxplot(x)
     par(mfrow=c(1,1))
     hdr.den(x)

