Variable Importance (VIMP) plot

Barplot displaying VIMP.

Usage

vimpPlot(vimp,
         Q_set = NULL,
         Time_Interaction = TRUE,
         xvar.names = NULL,
         cex.xlab = NULL,
         ymaxlim = 0,
         ymaxtimelim = 0,
         subhead.cexval = 1,
         yaxishead = NULL,
         xaxishead = NULL,
         main = "Variable Importance (%)",
         col = grey(0.8),
         cex.lab = 1.5,
         subhead.labels = c("Time-Interactions Effects", "Main Effects"),
         ylbl = FALSE,
         seplim = NULL,
         eps = 0.1,
         Width_Bar = 1,
         path_saveplot = NULL,
         Verbose = TRUE)

Arguments

vimp

VIMP values.

Q_set

Provide names for various levels of nominal or ordinal response.

Time_Interaction

Whether VIMP is estimated from a longitudinal data, in which case VIMP is available for covariate and covariate-time interaction. Default is TRUE. If FALSE, VIMP is assumed to be estimated from a cross-sectional data.

xvar.names

Names of the covariates. If NULL, names are assigned as x1, x2,...,xp.

cex.xlab

Magnification of the names of the covariates above (and below) the barplot.

ymaxlim

By default, we use the range of the vimp values for the covariates for the ylim. If one wants to extend the ylim, add the amount with which the ylim will extend above.

ymaxtimelim

By default, we use the range of the vimp values for the covariates-time for the ylim. If one wants to extend the ylim, add the amount with which the ylim will extend below. Argument only works for the longitudinal setting.

subhead.cexval

Magnification of the subhead.labels. Argument only works for the longitudinal setting.

yaxishead

This represent a vector with two values which are points on the y-axis. Corresponding to the values, the lables for subhead.labels is shown. First argument corresponds to covariate-time interaction, whereas second argument is for the main effect. Argument only works for the longitudinal setting.

xaxishead

This represent a vector with two values which are points on the x-axis. Corresponding to the values, the lables for subhead.labels is shown. First argument corresponds to covariate-time interaction, whereas second argument is for the main effect. Argument only works for the longitudinal setting.

main

Main title for the plot.

col

Color of the plot.

cex.lab

Magnification of the x and y lables.

subhead.labels

Labels corresponding to the plot. Default is "Time-Interactions Effects" for the barplot below x-axis, and "Main Effects" for the barplot above x-axis.

ylbl

Should labels for the sub-headings be shown on left side of the y-axis.

seplim

if ylbl is TRUE, the distance between the lables of the sub-headings.

eps

Amount of gap between the top of the barplot and variable names.

Width_Bar

Width of the barplot.

path_saveplot

Provide the location where plot should be saved. By default the plot will be saved at temporary folder.

Verbose

Display the path where the plot is saved?

Details

Barplot displaying VIMP. If the analysis is for the univariate case, VIMP is displayed above the x-axis. If the analysis is for the longitudinal case, VIMP for covariates (main effects) are shown above the x-axis while VIMP for covariate-time interactions (time interaction effects) are shown below the x-axis. In either case, negative vimp value is set to zero.

Author

Hemant Ishwaran, Amol Pande and Udaya B. Kogalur

Examples

if (FALSE) { # \dontrun{
##------------------------------------------------------------
## Synthetic example
## high correlation, quadratic time with quadratic interaction
##-------------------------------------------------------------
#simulate the data
dta <- simLong(n = 50, N = 5, rho =.80, model = 2,family = "Continuous")$dtaL

#basic boosting call
boost.grow <- boostmtree(dta$features, dta$time, dta$id, dta$y, 
              family = "Continuous",M = 300, cv.flag = TRUE)
vimp.grow <- vimp.boostmtree(object = boost.grow)              

# VIMP plot
vimpPlot(vimp = vimp.grow, ymaxlim = 20, ymaxtimelim = 20,
         xaxishead = c(3,3), yaxishead = c(65,65),
         cex.xlab = 1, subhead.cexval = 1.2)
} # }