Plot method for IWT results on functional on scalar linear model

plot method for class "IWTlm". Plotting function creating a graphical output of the IWT for the test on a functional on scalar linear model: functional data, and IWT-adjusted p-values of the F-tests on the whole model and of t-tests on all covariates' effects.

Usage

# S3 method for class 'IWTlm'
plot(
  x,
  xrange = c(0, 1),
  alpha1 = 0.05,
  alpha2 = 0.01,
  plot_adjpval = FALSE,
  col = c(1, grDevices::rainbow(dim(x$adjusted_pval_part)[1])),
  ylim = NULL,
  ylab = "Functional Data",
  main = NULL,
  lwd = 1,
  type = "l",
  ...
)

# S3 method for class 'TWTlm'
plot(
  x,
  xrange = c(0, 1),
  alpha1 = 0.05,
  alpha2 = 0.01,
  plot_adjpval = FALSE,
  col = c(1, grDevices::rainbow(dim(x$adjusted_pval_part)[1])),
  ylim = NULL,
  ylab = "Functional Data",
  main = NULL,
  lwd = 1,
  type = "l",
  ...
)

Arguments

x: The object to be plotted. An object of class "IWTlm", usually, a result of a call to IWTlm.
xrange: Range of the x axis.
alpha1: First level of significance used to select and display significant effects. Default is alpha1 = 0.05.
alpha2: Second level of significance used to select and display significant effects. Default is alpha1 = 0.01. alpha1 and alpha2 are s.t. alpha2 < alpha1. Otherwise the two values are switched.
plot_adjpval: A logical indicating wether the plots of adjusted p-values have to be done. Default is plot_adjpval = FALSE.
col: Colors for the plot of functional data. Default is col = 1.
ylim: Range of the y axis. Default is NULL, giving a plot with authomatic range for functional data.
ylab: Label of y axis of the plot of functional data. Default is "Functional Data".
main: An overall title for the plots (it will be pasted to "Functional Data and F-test" for the first plot and to covariates names for the other plots).
lwd: Line width for the plot of the adjusted p-value function. Default is lwd=1.
type: line type for the plot of the adjusted p-value function. Default is type='l'.
...: Additional plotting arguments that can be used with function plot, such as graphical parameters (see par).

Value

No value returned. The function produces a graphical output of the IWT results: the plot of the functional data and the one of the adjusted p-values. The portions of the domain selected as significant by the test at level alpha1 and alpha2 are highlighted in the plot of the adjusted p-value function and in the one of functional data by gray areas (light and dark gray, respectively). The first plot reports the gray areas corresponding to a significant F-test on the whole model. The remaining plots report the gray areas corresponding to significant t-tests on each covariate's effect.

References

Pini, A., & Vantini, S. (2017). Interval-wise testing for functional data. Journal of Nonparametric Statistics, 29(2), 407-424.

Pini, A., Vantini, S., Colosimo, B. M., & Grasso, M. (2018). Domain‐selective functional analysis of variance for supervised statistical profile monitoring of signal data. Journal of the Royal Statistical Society: Series C (Applied Statistics) 67(1), 55-81.

Abramowicz, K., Hager, C. K., Pini, A., Schelin, L., Sjostedt de Luna, S., & Vantini, S. (2018). Nonparametric inference for functional‐on‐scalar linear models applied to knee kinematic hop data after injury of the anterior cruciate ligament. Scandinavian Journal of Statistics 45(4), 1036-1061.

Examples

# Importing the NASA temperatures data set
data(NASAtemp)

temperature <- rbind(NASAtemp$milan, NASAtemp$paris)
groups <- c(rep(0, 22), rep(1, 22))

# Performing the IWT
IWT.result <- IWTlm(temperature ~ groups, B = 2L)
#> Error in eval(predvars, data, env): object 'groups' not found

# Summary of the IWT results
summary(IWT.result)
#> Error: object 'IWT.result' not found

# Plot of the IWT results
layout(1)
plot(IWT.result)
#> Error: object 'IWT.result' not found

# All graphics on the same device
layout(matrix(1:4, nrow = 2, byrow = FALSE))
plot(
  IWT.result, 
  main = 'NASA data', 
  plot_adjpval = TRUE, 
  xlab = 'Day', 
  xrange = c(1, 365)
)
#> Error: object 'IWT.result' not found