ALTopt (version 0.1.2)

pv.vdus.ic: VDUS (Variance Dispersion of Use Space) plot for interval censoring.

Description

pv.vdus.ic draws the VDUS plot of prediction variance for a given design with interval censoring plan. The use region (useLower and useUpper) should be provided.

Usage

pv.vdus.ic(
  design,
  t,
  k,
  nf,
  alpha,
  formula,
  coef,
  useLower = NULL,
  useUpper = NULL
)

Arguments

design

the data frame containing the coordinates and the number of allocation of each design point. The design created by either altopt.rc or altopt.ic or any design matrix with the same form as those can be provided for this argument.

t

the total testing time.

k

the number of time intervals.

nf

the number of stress factors.

alpha

the value of the shape parameter of Weibull distribution.

formula

the object of class formula which is the linear predictor model.

coef

the numeric vector containing the coefficients of each term in formula.

useLower, useUpper

the vectors containing the lower bound and upper bound for the use region. They should be provided for VDUS plot.

Value

The "trellis" object which includes the VDUS plot for interval censoring.

See Also

altopt.ic

Examples

# NOT RUN {
# VDUS plot of I optimal design with interval censoring.
Design <- altopt.ic("I", 100, 30, 5, 2, 1, formula = ~ x1 + x2 + x1:x2,
coef = c(0, -4.086, -1.476, 0.01), useLower = c(1.458, 2.859), useUpper = c(2.058, 3.459))

pv.vdus.ic(Design$opt.design.rounded, 30, 5, 2, 1,
formula = ~ x1 + x2 + x1:x2, coef = c(0, -4.086, -1.476, 0.01),
useLower = c(1.458, 2.859), useUpper = c(2.058, 3.459))
# }