Diagnostic Plots for islasso Models — plot.islasso • islasso

Produces standard diagnostic plots for a fitted islasso model to assess residuals, model fit, and variance structure.

Usage

# S3 method for class 'islasso'
plot(x, ...)

Arguments

x: An object of class "islasso", typically created via islasso.
...: Additional graphical parameters passed to the underlying plot() functions.

Details

Generates a 2x2 grid of diagnostic plots:

Top-left: Deviance residuals vs fitted values.
Top-right: Normal Q-Q plot of standardized deviance residuals (red line = reference).
Bottom-left: Squared standardized Pearson residuals vs fitted values.
Bottom-right: Working response vector vs linear predictor.

These plots help assess the assumptions of linearity, homoscedasticity, and residual normality in penalized regression.

See also

islasso, summary.islasso, residuals.islasso, logLik.islasso, predict.islasso, deviance.islasso

Author

Gianluca Sottile gianluca.sottile@unipa.it

Examples

if (FALSE) { # \dontrun{
  set.seed(1)
  n <- 100; p <- 100
  beta <- c(runif(20, -3, 3), rep(0, p - 20))
  sim <- simulXy(n = n, p = p, beta = beta, seed = 1, family = gaussian())
  fit <- islasso(y ~ ., data = sim$data, family = gaussian(), lambda = 2)
  plot(fit)
} # }