## ----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" = 100L) options("mlexperiments.optim.xgb.early_stopping_rounds" = 10L) ## ----------------------------------------------------------------------------- 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$test, get("time")], type = "right" ) ## ----------------------------------------------------------------------------- fold_list <- splitTools::create_folds( y = split_vector_train, k = 3, type = "stratified", seed = seed ) ## ----------------------------------------------------------------------------- # required learner arguments, not optimized learner_args <- list( objective = "survival:cox", eval_metric = "cox-nloglik" ) # set arguments for predict function and performance metric, # required for mlexperiments::MLCrossValidation and # mlexperiments::MLNestedCV predict_args <- NULL performance_metric <- c_index performance_metric_args <- NULL return_models <- FALSE # required for grid search and initialization of bayesian optimization parameter_grid <- expand.grid( subsample = seq(0.6, 1, .2), colsample_bytree = seq(0.6, 1, .2), min_child_weight = seq(1, 5, 4), learning_rate = seq(0.1, 0.2, 0.1), max_depth = seq(1, 5, 4) ) # reduce to a maximum of 10 rows if (nrow(parameter_grid) > 10) { set.seed(123) sample_rows <- sample(seq_len(nrow(parameter_grid)), 10, FALSE) parameter_grid <- kdry::mlh_subset(parameter_grid, sample_rows) } # required for bayesian optimization parameter_bounds <- list( subsample = c(0.2, 1), colsample_bytree = c(0.2, 1), min_child_weight = c(1L, 10L), learning_rate = c(0.1, 0.2), max_depth = c(1L, 10L) ) optim_args <- list( iters.n = ncores, kappa = 3.5, acq = "ucb" ) ## ----------------------------------------------------------------------------- tuner <- mlexperiments::MLTuneParameters$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$execute(k = 3) #> #> Parameter settings [==============================================================================================================>----------------------------] 8/10 ( 80%) #> Parameter settings [============================================================================================================================>--------------] 9/10 ( 90%) #> Parameter settings [==========================================================================================================================================] 10/10 (100%) head(tuner_results_grid) #> setting_id metric_optim_mean nrounds subsample colsample_bytree min_child_weight learning_rate max_depth objective eval_metric #> 1: 1 4.866125 26 0.6 0.8 5 0.2 1 survival:cox cox-nloglik #> 2: 2 4.896370 14 1.0 0.8 5 0.1 5 survival:cox cox-nloglik #> 3: 3 4.860956 72 0.8 0.8 5 0.1 1 survival:cox cox-nloglik #> 4: 4 4.867604 6 0.6 0.8 5 0.2 5 survival:cox cox-nloglik #> 5: 5 4.893917 14 1.0 0.8 1 0.1 5 survival:cox cox-nloglik #> 6: 6 4.883471 13 0.8 0.8 5 0.1 5 survival:cox cox-nloglik ## ----------------------------------------------------------------------------- tuner <- mlexperiments::MLTuneParameters$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$execute(k = 3) #> #> Registering parallel backend using 4 cores. head(tuner_results_bayesian) #> Epoch setting_id subsample colsample_bytree min_child_weight learning_rate max_depth gpUtility acqOptimum inBounds Elapsed Score metric_optim_mean nrounds errorMessage #> 1: 0 1 0.6 0.8 5 0.2 1 NA FALSE TRUE 1.792 -4.867594 4.867594 22 NA #> 2: 0 2 1.0 0.8 5 0.1 5 NA FALSE TRUE 1.826 -4.901912 4.901912 12 NA #> 3: 0 3 0.8 0.8 5 0.1 1 NA FALSE TRUE 1.833 -4.874152 4.874152 48 NA #> 4: 0 4 0.6 0.8 5 0.2 5 NA FALSE TRUE 1.836 -4.870687 4.870687 5 NA #> 5: 0 5 1.0 0.8 1 0.1 5 NA FALSE TRUE 0.813 -4.883240 4.883240 14 NA #> 6: 0 6 0.8 0.8 5 0.1 5 NA FALSE TRUE 0.861 -4.895220 4.895220 13 NA #> objective eval_metric #> 1: survival:cox cox-nloglik #> 2: survival:cox cox-nloglik #> 3: survival:cox cox-nloglik #> 4: survival:cox cox-nloglik #> 5: survival:cox cox-nloglik #> 6: survival:cox cox-nloglik ## ----------------------------------------------------------------------------- validator <- mlexperiments::MLCrossValidation$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 objective eval_metric #> 1: Fold1 0.6433838 0.3015909 0.5804647 1 0.2 1 27 survival:cox cox-nloglik #> 2: Fold2 0.6979611 0.3015909 0.5804647 1 0.2 1 27 survival:cox cox-nloglik #> 3: Fold3 0.6536441 0.3015909 0.5804647 1 0.2 1 27 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 objective eval_metric #> 1: Fold1 0.6355074 47 0.6 1.0 1 0.2 1 survival:cox cox-nloglik #> 2: Fold2 0.6699094 13 0.8 0.8 5 0.1 5 survival:cox cox-nloglik #> 3: Fold3 0.6832026 20 0.6 0.8 5 0.2 1 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 objective eval_metric #> 1: Fold1 0.6420432 0.6394793 0.9881643 4 0.1268116 1 53 survival:cox cox-nloglik #> 2: Fold2 0.6563499 1.0000000 1.0000000 5 0.1000000 5 11 survival:cox cox-nloglik #> 3: Fold3 0.6573680 0.7495501 0.4383327 7 0.1000000 5 20 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 0.6384856 #> 2: Fold2 0.6118066 #> 3: Fold3 0.6356952 ## ----include=FALSE------------------------------------------------------------ # nolint end