## ----setup-------------------------------------------------------------------- # nolint start library(mlexperiments) library(mlsurvlrnrs) ## ----------------------------------------------------------------------------- dataset <- survival::colon |> data.table::as.data.table() |> na.omit() dataset <- dataset[get("etype") == 2, ] surv_cols <- c("status", "time", "rx") feature_cols <- colnames(dataset)[3:(ncol(dataset) - 1)] ## ----------------------------------------------------------------------------- seed <- 123 if (isTRUE(as.logical(Sys.getenv("_R_CHECK_LIMIT_CORES_")))) { # on cran ncores <- 2L } else { ncores <- ifelse( test = parallel::detectCores() > 4, yes = 4L, no = ifelse( test = parallel::detectCores() < 2L, yes = 1L, no = parallel::detectCores() ) ) } options("mlexperiments.bayesian.max_init" = 10L) options("mlexperiments.optim.xgb.nrounds" = 20L) options("mlexperiments.optim.xgb.early_stopping_rounds" = 5L) ## ----------------------------------------------------------------------------- split_vector <- splitTools::multi_strata( df = dataset[, .SD, .SDcols = surv_cols], strategy = "kmeans", k = 4 ) data_split <- splitTools::partition( y = split_vector, p = c(train = 0.7, test = 0.3), type = "stratified", seed = seed ) train_x <- model.matrix( ~ -1 + ., dataset[ data_split$train, .SD, .SDcols = setdiff(feature_cols, surv_cols[1:2]) ] ) train_y <- survival::Surv( event = (dataset[data_split$train, get("status")] |> as.character() |> as.integer()), time = dataset[data_split$train, get("time")], type = "right" ) split_vector_train <- splitTools::multi_strata( df = dataset[data_split$train, .SD, .SDcols = surv_cols], strategy = "kmeans", k = 4 ) test_x <- model.matrix( ~ -1 + ., dataset[data_split$test, .SD, .SDcols = setdiff(feature_cols, surv_cols[1:2])] ) test_y <- survival::Surv( event = (dataset[data_split$test, get("status")] |> as.character() |> as.integer()), time = dataset[data_split$test, get("time")], type = "right" ) ## ----------------------------------------------------------------------------- fold_list <- splitTools::create_folds( y = split_vector_train, k = 3, type = "stratified", seed = seed ) ## ----------------------------------------------------------------------------- # required learner arguments, not optimized learner_args <- list( objective = "survival:cox", eval_metric = "cox-nloglik" ) # set arguments for predict function and performance metric, # required for mlexperiments::MLCrossValidation and # mlexperiments::MLNestedCV predict_args <- NULL performance_metric <- c_index performance_metric_args <- NULL return_models <- FALSE # required for grid search and initialization of bayesian optimization parameter_grid <- expand.grid( subsample = seq(0.6, 1, .2), colsample_bytree = seq(0.6, 1, .2), min_child_weight = seq(1, 5, 4), learning_rate = seq(0.1, 0.2, 0.1), max_depth = seq(1, 5, 4) ) # reduce to a maximum of 10 rows if (nrow(parameter_grid) > 10) { set.seed(123) sample_rows <- sample(seq_len(nrow(parameter_grid)), 10, FALSE) parameter_grid <- kdry::mlh_subset(parameter_grid, sample_rows) } # required for bayesian optimization parameter_bounds <- list( subsample = c(0.2, 1), colsample_bytree = c(0.2, 1), min_child_weight = c(1L, 10L), learning_rate = c(0.1, 0.2), max_depth = c(1L, 10L) ) optim_args <- list( n_iter = ncores, kappa = 3.5, acq = "ucb" ) ## ----------------------------------------------------------------------------- tuner <- mlexperiments::MLTuneParameters$new( learner = LearnerSurvXgboostCox$new( metric_optimization_higher_better = FALSE ), strategy = "grid", ncores = ncores, seed = seed ) tuner$parameter_grid <- parameter_grid tuner$learner_args <- learner_args tuner$split_type <- "stratified" tuner$split_vector <- split_vector_train tuner$set_data( x = train_x, y = train_y ) tuner_results_grid <- tuner$execute(k = 3) #> #> Parameter settings [==============================================================================================================>----------------------------] 8/10 ( 80%) #> Parameter settings [============================================================================================================================>--------------] 9/10 ( 90%) #> Parameter settings [==========================================================================================================================================] 10/10 (100%) head(tuner_results_grid) #> setting_id metric_optim_mean nrounds subsample colsample_bytree min_child_weight learning_rate #> #> 1: 1 4.846400 37 0.6 0.8 5 0.2 #> 2: 2 4.862686 10 1.0 0.8 5 0.1 #> 3: 3 4.852380 41 0.8 0.8 5 0.1 #> 4: 4 4.875127 7 0.6 0.8 5 0.2 #> 5: 5 4.897189 7 1.0 0.8 1 0.1 #> 6: 6 4.854463 10 0.8 0.8 5 0.1 #> max_depth objective eval_metric #> #> 1: 1 survival:cox cox-nloglik #> 2: 5 survival:cox cox-nloglik #> 3: 1 survival:cox cox-nloglik #> 4: 5 survival:cox cox-nloglik #> 5: 5 survival:cox cox-nloglik #> 6: 5 survival:cox cox-nloglik ## ----------------------------------------------------------------------------- tuner <- mlexperiments::MLTuneParameters$new( learner = LearnerSurvXgboostCox$new( metric_optimization_higher_better = FALSE ), strategy = "bayesian", ncores = ncores, seed = seed ) tuner$parameter_grid <- parameter_grid tuner$parameter_bounds <- parameter_bounds tuner$learner_args <- learner_args tuner$optim_args <- optim_args tuner$split_type <- "stratified" tuner$split_vector <- split_vector_train tuner$set_data( x = train_x, y = train_y ) tuner_results_bayesian <- tuner$execute(k = 3) #> #> Registering parallel backend using 4 cores. head(tuner_results_bayesian) #> Epoch setting_id subsample colsample_bytree min_child_weight learning_rate max_depth gpUtility #> #> 1: 0 1 0.6 0.8 5 0.2 1 NA #> 2: 0 2 1.0 0.8 5 0.1 5 NA #> 3: 0 3 0.8 0.8 5 0.1 1 NA #> 4: 0 4 0.6 0.8 5 0.2 5 NA #> 5: 0 5 1.0 0.8 1 0.1 5 NA #> 6: 0 6 0.8 0.8 5 0.1 5 NA #> acqOptimum inBounds Elapsed Score metric_optim_mean nrounds errorMessage objective #> #> 1: FALSE TRUE 0.947 -4.846400 4.846400 37 NA survival:cox #> 2: FALSE TRUE 0.945 -4.862686 4.862686 10 NA survival:cox #> 3: FALSE TRUE 0.925 -4.852380 4.852380 41 NA survival:cox #> 4: FALSE TRUE 0.817 -4.875127 4.875127 7 NA survival:cox #> 5: FALSE TRUE 0.081 -4.897189 4.897189 7 NA survival:cox #> 6: FALSE TRUE 0.124 -4.854463 4.854463 10 NA survival:cox #> eval_metric #> #> 1: cox-nloglik #> 2: cox-nloglik #> 3: cox-nloglik #> 4: cox-nloglik #> 5: cox-nloglik #> 6: cox-nloglik ## ----------------------------------------------------------------------------- validator <- mlexperiments::MLCrossValidation$new( learner = LearnerSurvXgboostCox$new( metric_optimization_higher_better = FALSE ), fold_list = fold_list, ncores = ncores, seed = seed ) validator$learner_args <- tuner$results$best.setting[-1] validator$predict_args <- predict_args validator$performance_metric <- performance_metric validator$performance_metric_args <- performance_metric_args validator$return_models <- return_models validator$set_data( x = train_x, y = train_y ) validator_results <- validator$execute() #> #> CV fold: Fold1 #> #> CV fold: Fold2 #> #> CV fold: Fold3 head(validator_results) #> fold performance subsample colsample_bytree min_child_weight learning_rate max_depth nrounds #> #> 1: Fold1 0.6581185 0.6 0.8 5 0.2 1 37 #> 2: Fold2 0.6584779 0.6 0.8 5 0.2 1 37 #> 3: Fold3 0.6291327 0.6 0.8 5 0.2 1 37 #> objective eval_metric #> #> 1: survival:cox cox-nloglik #> 2: survival:cox cox-nloglik #> 3: survival:cox cox-nloglik ## ----------------------------------------------------------------------------- validator <- mlexperiments::MLNestedCV$new( learner = LearnerSurvXgboostCox$new( metric_optimization_higher_better = FALSE ), strategy = "grid", fold_list = fold_list, k_tuning = 3L, ncores = ncores, seed = seed ) validator$parameter_grid <- parameter_grid validator$learner_args <- learner_args validator$split_type <- "stratified" validator$split_vector <- split_vector_train validator$predict_args <- predict_args validator$performance_metric <- performance_metric validator$performance_metric_args <- performance_metric_args validator$return_models <- return_models validator$set_data( x = train_x, y = train_y ) validator_results <- validator$execute() #> #> CV fold: Fold1 #> #> Parameter settings [==============================================================================================================>----------------------------] 8/10 ( 80%) #> Parameter settings [============================================================================================================================>--------------] 9/10 ( 90%) #> Parameter settings [==========================================================================================================================================] 10/10 (100%) #> CV fold: Fold2 #> CV progress [=================================================================================================>-------------------------------------------------] 2/3 ( 67%) #> #> Parameter settings [=====================================================================>---------------------------------------------------------------------] 5/10 ( 50%) #> Parameter settings [==================================================================================>--------------------------------------------------------] 6/10 ( 60%) #> Parameter settings [================================================================================================>------------------------------------------] 7/10 ( 70%) #> Parameter settings [==============================================================================================================>----------------------------] 8/10 ( 80%) #> Parameter settings [============================================================================================================================>--------------] 9/10 ( 90%) #> Parameter settings [==========================================================================================================================================] 10/10 (100%) #> CV fold: Fold3 #> CV progress [===================================================================================================================================================] 3/3 (100%) #> #> Parameter settings [=======================================================>-----------------------------------------------------------------------------------] 4/10 ( 40%) #> Parameter settings [=====================================================================>---------------------------------------------------------------------] 5/10 ( 50%) #> Parameter settings [==================================================================================>--------------------------------------------------------] 6/10 ( 60%) #> Parameter settings [================================================================================================>------------------------------------------] 7/10 ( 70%) #> Parameter settings [==============================================================================================================>----------------------------] 8/10 ( 80%) #> Parameter settings [============================================================================================================================>--------------] 9/10 ( 90%) #> Parameter settings [==========================================================================================================================================] 10/10 (100%) head(validator_results) #> fold performance nrounds subsample colsample_bytree min_child_weight learning_rate max_depth #> #> 1: Fold1 0.6519473 23 0.6 0.8 5 0.2 1 #> 2: Fold2 0.6227989 11 0.6 1.0 1 0.2 1 #> 3: Fold3 0.6508312 54 0.8 0.8 5 0.1 1 #> objective eval_metric #> #> 1: survival:cox cox-nloglik #> 2: survival:cox cox-nloglik #> 3: survival:cox cox-nloglik ## ----------------------------------------------------------------------------- validator <- mlexperiments::MLNestedCV$new( learner = LearnerSurvXgboostCox$new( metric_optimization_higher_better = FALSE ), strategy = "bayesian", fold_list = fold_list, k_tuning = 3L, ncores = ncores, seed = 312 ) validator$parameter_grid <- parameter_grid validator$learner_args <- learner_args validator$split_type <- "stratified" validator$split_vector <- split_vector_train validator$parameter_bounds <- parameter_bounds validator$optim_args <- optim_args validator$predict_args <- predict_args validator$performance_metric <- performance_metric validator$performance_metric_args <- performance_metric_args validator$return_models <- TRUE validator$set_data( x = train_x, y = train_y ) validator_results <- validator$execute() #> #> CV fold: Fold1 #> #> Registering parallel backend using 4 cores. #> #> CV fold: Fold2 #> CV progress [=================================================================================================>-------------------------------------------------] 2/3 ( 67%) #> #> Registering parallel backend using 4 cores. #> #> CV fold: Fold3 #> CV progress [===================================================================================================================================================] 3/3 (100%) #> #> Registering parallel backend using 4 cores. head(validator_results) #> fold performance subsample colsample_bytree min_child_weight learning_rate max_depth nrounds #> #> 1: Fold1 0.6491018 0.6 1.0 1 0.2000000 1 24 #> 2: Fold2 0.6473323 0.6 0.8 5 0.2000000 1 17 #> 3: Fold3 0.6295374 1.0 0.8 6 0.1592348 5 8 #> objective eval_metric #> #> 1: survival:cox cox-nloglik #> 2: survival:cox cox-nloglik #> 3: survival:cox cox-nloglik ## ----------------------------------------------------------------------------- preds_xgboost <- mlexperiments::predictions( object = validator, newdata = test_x ) ## ----------------------------------------------------------------------------- perf_xgboost <- mlexperiments::performance( object = validator, prediction_results = preds_xgboost, y_ground_truth = test_y ) perf_xgboost #> model performance #> #> 1: Fold1 0.6531627 #> 2: Fold2 0.6421748 #> 3: Fold3 0.6318355 ## ----include=FALSE------------------------------------------------------------ # nolint end