Sparse Group LASSO regularization for survival analysis
Usage
sparsegrouplasso(
  data,
  time_var,
  event_var,
  pred_vars,
  group_definition = "factor_based",
  custom_groups = "",
  pathway_info,
  correlation_threshold = 0.7,
  alpha_sgl = 0.95,
  lambda_sequence = "auto",
  custom_lambda = "",
  lambda_min_ratio = 0.001,
  n_lambda = 100,
  selection_criterion = "cv_deviance",
  cv_folds = 10,
  cv_repeats = 1,
  ebic_gamma = 1,
  weight_type = "none",
  weight_power = 1,
  standardize_vars = TRUE,
  center_vars = TRUE,
  orthogonalize_groups = FALSE,
  max_iterations = 1000,
  convergence_threshold = 1e-06,
  warm_start = TRUE,
  parallel_cv = FALSE,
  seed_value = 42,
  show_summary = TRUE,
  show_coefficients = TRUE,
  show_groups = TRUE,
  show_path = FALSE,
  show_performance = TRUE,
  show_validation = TRUE,
  plot_cv_error = TRUE,
  plot_coefficients = TRUE,
  plot_groups = TRUE,
  plot_sparsity = FALSE,
  plot_stability = FALSE,
  alpha_level = 0.05,
  confidence_intervals = FALSE,
  bootstrap_samples = 500,
  stability_selection = FALSE,
  stability_threshold = 0.8,
  stability_subsample = 0.8,
  showExplanations = TRUE
)Arguments
- data
- the data as a data frame 
- time_var
- the time-to-event variable 
- event_var
- the event indicator variable (0/1 or FALSE/TRUE) 
- pred_vars
- the predictor variables for the model 
- group_definition
- method for defining variable groups 
- custom_groups
- custom group specification as comma-separated lists. Example: "1,2;3,4,5;6" for three groups 
- pathway_info
- variable containing pathway/cluster information for grouping 
- correlation_threshold
- correlation threshold for correlation-based grouping 
- alpha_sgl
- mixing parameter between group LASSO (0) and LASSO (1). Default 0.95 emphasizes sparsity within groups 
- lambda_sequence
- method for selecting regularization parameter sequence 
- custom_lambda
- custom lambda values as comma-separated numbers. Example: "0.001,0.01,0.1,1" 
- lambda_min_ratio
- ratio of smallest to largest lambda value 
- n_lambda
- number of lambda values in the sequence 
- selection_criterion
- criterion for selecting optimal lambda 
- cv_folds
- number of folds for cross-validation 
- cv_repeats
- number of repeated cross-validation runs 
- ebic_gamma
- gamma parameter for Extended BIC (0 = standard BIC) 
- weight_type
- type of adaptive weights for penalty terms 
- weight_power
- power parameter for adaptive weights 
- standardize_vars
- whether to standardize predictor variables 
- center_vars
- whether to center predictor variables 
- orthogonalize_groups
- whether to orthogonalize variables within groups 
- max_iterations
- maximum number of iterations for optimization 
- convergence_threshold
- convergence threshold for optimization 
- warm_start
- whether to use warm start for lambda sequence 
- parallel_cv
- whether to use parallel processing for CV 
- seed_value
- random seed for reproducible results 
- show_summary
- show model summary table 
- show_coefficients
- show coefficient estimates table 
- show_groups
- show group structure table 
- show_path
- show complete regularization path 
- show_performance
- show model performance metrics 
- show_validation
- show cross-validation results 
- plot_cv_error
- plot cross-validation error curve 
- plot_coefficients
- plot coefficient regularization path 
- plot_groups
- plot group selection pattern 
- plot_sparsity
- plot sparsity pattern across lambda values 
- plot_stability
- plot stability selection results 
- alpha_level
- significance level for confidence intervals 
- confidence_intervals
- whether to calculate bootstrap confidence intervals 
- bootstrap_samples
- number of bootstrap samples for confidence intervals 
- stability_selection
- whether to perform stability selection 
- stability_threshold
- threshold for stability selection 
- stability_subsample
- subsample ratio for stability selection 
- showExplanations
- show explanations for the analysis 
Value
A results object containing:
| results$instructions | a html | ||||
| results$todo | a html | ||||
| results$summary | a table | ||||
| results$coefficients | a table | ||||
| results$groupStructure | a table | ||||
| results$solutionPath | a table | ||||
| results$performance | a table | ||||
| results$validationResults | a table | ||||
| results$adaptiveWeights | a table | ||||
| results$stabilityResults | a table | ||||
| results$comparisonTable | a table | ||||
| results$cvErrorPlot | an image | ||||
| results$coefficientPlot | an image | ||||
| results$groupSelectionPlot | an image | ||||
| results$sparsityPlot | an image | ||||
| results$stabilityPlot | an image | ||||
| results$explanations | a html | 
Tables can be converted to data frames with asDF or as.data.frame. For example:
results$summary$asDF
as.data.frame(results$summary)