| Title: | Ensemble Learning Framework for Diagnostic and Prognostic Modeling |
| Version: | 0.1.1 |
| Description: | Provides a framework to build and evaluate diagnosis or prognosis models using stacking, voting, and bagging ensemble techniques with various base learners. The package also includes tools for visualization and interpretation of models. The development version of the package is available on 'GitHub' at https://github.com/xiaojie0519/E2E. The methods are based on the foundational work of Breiman (1996) <doi:10.1007/BF00058655> on bagging and Wolpert (1992) <doi:10.1016/S0893-6080(05)80023-1> on stacking. |
| License: | MIT + file LICENSE |
| Encoding: | UTF-8 |
| URL: | https://xiaojie0519.github.io/E2E/ |
| BugReports: | https://github.com/xiaojie0519/E2E/issues |
| RoxygenNote: | 7.3.2 |
| Imports: | caret, dplyr, tidyr, gbm, ggplot2, glmnet, magrittr, MASS, patchwork, pROC, PRROC, randomForestSRC, readr, RSNNS, shapviz, survcomp, survival, survivalROC, survminer, timeROC, xgboost, plsRcox, cowplot, |
| Suggests: | ada, doParallel, e1071, kernlab, klaR, knitr, nnet, randomForest, RColorBrewer, rmarkdown, rpart, |
| Depends: | R (≥ 3.5) |
| LazyData: | true |
| VignetteBuilder: | knitr |
| Language: | en |
| NeedsCompilation: | no |
| Packaged: | 2025-11-28 14:26:55 UTC; Lenovo |
| Author: | Shanjie Luan [aut, cre] |
| Maintainer: | Shanjie Luan <Luan20050519@163.com> |
| Repository: | CRAN |
| Date/Publication: | 2025-11-28 15:20:02 UTC |
re-export Surv from survival
Description
re-export Surv from survival
Apply a Trained Model to New Data
Description
Applies a trained diagnostic model (single or ensemble) to a new dataset to generate predictions. It can handle various model objects created by the package, including single caret models, Bagging, Stacking, Voting, and EasyEnsemble objects.
Usage
apply_dia(
trained_model_object,
new_data,
label_col_name = NULL,
pos_class = "Positive",
neg_class = "Negative"
)
Arguments
trained_model_object |
A trained model object from |
new_data |
A data frame containing the new samples for prediction. The first column must be the sample ID. |
label_col_name |
An optional character string specifying the name of the
column in |
pos_class |
A character string for the positive class label used in the
model's probability predictions. Defaults to |
neg_class |
A character string for the negative class label. This parameter
is mainly for consistency, as prediction focuses on |
Value
A data frame with three columns: sample (the sample IDs), label
(the true labels from new_data, or NA if not available/specified), and score
(the predicted probability for the positive class).
Examples
# Assuming `bagging_results` and `test_dia` are available from previous steps
# bagging_model <- bagging_results$model_object
# Example 1: Default behavior - use the second column of test_dia as label
# predictions <- apply_dia(
# trained_model_object = bagging_model,
# new_data = test_dia
# )
# Example 2: Explicitly specify the label column by name
# predictions_explicit <- apply_dia(
# trained_model_object = bagging_model,
# new_data = test_dia,
# label_col_name = "outcome"
# )
# Example 3: Predict on data without labels
# test_data_no_labels <- test_dia[, -2] # Remove outcome column
# predictions_no_label <- apply_dia(
# trained_model_object = bagging_model,
# new_data = test_data_no_labels,
# label_col_name = NA # Explicitly disable label extraction
# )
Apply Prognostic Model to New Data
Description
Generates risk scores for new patients using a trained model.
Usage
apply_pro(trained_model_object, new_data, time_unit = "day")
Arguments
trained_model_object |
A trained object (class |
new_data |
Data frame of new patients. |
time_unit |
Time unit for data preparation. |
Value
Data frame with IDs, outcomes (if available), and risk scores.
Train a Bagging Diagnostic Model
Description
Implements a Bagging (Bootstrap Aggregating) ensemble for diagnostic models. It trains multiple base models on bootstrapped samples of the training data and aggregates their predictions by averaging probabilities.
Usage
bagging_dia(
data,
base_model_name,
n_estimators = 50,
subset_fraction = 0.632,
tune_base_model = FALSE,
threshold_choices = "default",
positive_label_value = 1,
negative_label_value = 0,
new_positive_label = "Positive",
new_negative_label = "Negative",
seed = 456
)
Arguments
data |
A data frame where the first column is the sample ID, the second is the outcome label, and subsequent columns are features. |
base_model_name |
A character string, the name of the base diagnostic model to use (e.g., "rf", "lasso"). This model must be registered. |
n_estimators |
An integer, the number of base models to train. |
subset_fraction |
A numeric value between 0 and 1, the fraction of samples to bootstrap for each base model. |
tune_base_model |
Logical, whether to enable tuning for each base model. |
threshold_choices |
A character string (e.g., "f1", "youden", "default") or a numeric value (0-1) for determining the evaluation threshold for the ensemble. |
positive_label_value |
A numeric or character value in the raw data representing the positive class. |
negative_label_value |
A numeric or character value in the raw data representing the negative class. |
new_positive_label |
A character string, the desired factor level name for the positive class (e.g., "Positive"). |
new_negative_label |
A character string, the desired factor level name for the negative class (e.g., "Negative"). |
seed |
An integer, for reproducibility. |
Value
A list containing the model_object, sample_score, and evaluation_metrics.
See Also
initialize_modeling_system_dia, evaluate_model_dia
Examples
# This example assumes your package includes a dataset named 'train_dia'.
# If not, create a toy data frame first.
if (exists("train_dia")) {
initialize_modeling_system_dia()
bagging_rf_results <- bagging_dia(
data = train_dia,
base_model_name = "rf",
n_estimators = 5, # Reduced for a quick example
threshold_choices = "youden",
positive_label_value = 1,
negative_label_value = 0,
new_positive_label = "Case",
new_negative_label = "Control"
)
print_model_summary_dia("Bagging (RF)", bagging_rf_results)
}
Train Bagging Ensemble for Prognosis
Description
Implements Bootstrap Aggregating (Bagging) for survival models. It trains multiple base models on bootstrapped subsets and averages the risk scores. This method reduces variance and improves stability.
Usage
bagging_pro(
data,
base_model_name,
n_estimators = 10,
subset_fraction = 0.632,
tune_base_model = FALSE,
time_unit = "day",
years_to_evaluate = c(1, 3, 5),
seed = 456
)
Arguments
data |
Input data frame (ID, Status, Time, Features). |
base_model_name |
Character string name of the base model (e.g., "rsf_pro"). |
n_estimators |
Integer. Number of bootstrap iterations. |
subset_fraction |
Numeric (0-1). Fraction of data to sample in each iteration. |
tune_base_model |
Logical. Whether to tune each base model (computationally expensive). |
time_unit |
Time unit of the input data. |
years_to_evaluate |
Numeric vector of years for time-dependent AUC evaluation. |
seed |
Integer seed for reproducibility. |
Value
A list containing the ensemble object, sample scores, and evaluation metrics.
Calculate Classification Metrics at a Specific Threshold
Description
Calculates various classification performance metrics (Accuracy, Precision, Recall, F1-score, Specificity, True Positives, etc.) for binary classification at a given probability threshold.
Usage
calculate_metrics_at_threshold_dia(
prob_positive,
y_true,
threshold,
pos_class,
neg_class
)
Arguments
prob_positive |
A numeric vector of predicted probabilities for the positive class. |
y_true |
A factor vector of true class labels. |
threshold |
A numeric value between 0 and 1, the probability threshold above which a prediction is considered positive. |
pos_class |
A character string, the label for the positive class. |
neg_class |
A character string, the label for the negative class. |
Value
A list containing:
-
Threshold: The threshold used. -
Accuracy: Overall prediction accuracy. -
Precision: Precision for the positive class. -
Recall: Recall (Sensitivity) for the positive class. -
F1: F1-score for the positive class. -
Specificity: Specificity for the negative class. -
TP,TN,FP,FN,N: Counts of True Positives, True Negatives, False Positives, False Negatives, and total samples.
Examples
y_true_ex <- factor(c("Negative", "Positive", "Positive", "Negative", "Positive"),
levels = c("Negative", "Positive"))
prob_ex <- c(0.1, 0.8, 0.6, 0.3, 0.9)
metrics <- calculate_metrics_at_threshold_dia(
prob_positive = prob_ex,
y_true = y_true_ex,
threshold = 0.5,
pos_class = "Positive",
neg_class = "Negative"
)
print(metrics)
Train a Decision Tree Model for Classification
Description
Trains a single Decision Tree model using caret::train (via rpart method)
for binary classification.
Usage
dt_dia(X, y, tune = FALSE, cv_folds = 5)
Arguments
X |
A data frame of features. |
y |
A factor vector of class labels. |
tune |
Logical, whether to perform hyperparameter tuning for |
cv_folds |
An integer, the number of cross-validation folds for |
Value
A caret::train object representing the trained Decision Tree model.
Examples
set.seed(42)
n_obs <- 50
X_toy <- data.frame(
FeatureA = rnorm(n_obs),
FeatureB = runif(n_obs, 0, 100)
)
y_toy <- factor(sample(c("Control", "Case"), n_obs, replace = TRUE),
levels = c("Control", "Case"))
# Train the model
dt_model <- dt_dia(X_toy, y_toy)
print(dt_model)
Train an Elastic Net (L1 and L2 Regularized Logistic Regression) Model for Classification
Description
Trains an Elastic Net-regularized logistic regression model
using caret::train (via glmnet method) for binary classification.
Usage
en_dia(X, y, tune = FALSE, cv_folds = 5)
Arguments
X |
A data frame of features. |
y |
A factor vector of class labels. |
tune |
Logical, whether to perform hyperparameter tuning for |
cv_folds |
An integer, the number of cross-validation folds for |
Value
A caret::train object representing the trained Elastic Net model.
Examples
set.seed(42)
n_obs <- 50
X_toy <- data.frame(
FeatureA = rnorm(n_obs),
FeatureB = runif(n_obs, 0, 100)
)
y_toy <- factor(sample(c("Control", "Case"), n_obs, replace = TRUE),
levels = c("Control", "Case"))
# Train the model
en_model <- en_dia(X_toy, y_toy)
print(en_model)
Train Elastic Net Cox Model
Description
Fits a Cox model with Elastic Net regularization (mixture of L1 and L2 penalties). Alpha is fixed at 0.5.
Usage
en_pro(X, y_surv, tune = FALSE)
Arguments
X |
A data frame of predictors. |
y_surv |
A |
tune |
Logical. If TRUE, performs internal tuning (currently handled by cv.glmnet automatically). |
Value
An object of class survival_glmnet and pro_model.
Evaluate Diagnostic Model Performance
Description
Evaluates the performance of a trained diagnostic model using various metrics relevant to binary classification, including AUROC, AUPRC, and metrics at an optimal or specified probability threshold.
Usage
evaluate_model_dia(
model_obj = NULL,
X_data = NULL,
y_data,
sample_ids,
threshold_choices = "default",
pos_class,
neg_class,
precomputed_prob = NULL,
y_original_numeric = NULL
)
Arguments
model_obj |
A trained model object (typically a |
X_data |
A data frame of features corresponding to the data used for evaluation.
Required if |
y_data |
A factor vector of true class labels for the evaluation data. |
sample_ids |
A vector of sample IDs for the evaluation data. |
threshold_choices |
A character string specifying the thresholding strategy ("default", "f1", "youden") or a numeric probability threshold value (0-1). |
pos_class |
A character string, the label for the positive class. |
neg_class |
A character string, the label for the negative class. |
precomputed_prob |
Optional. A numeric vector of precomputed probabilities
for the positive class. If provided, |
y_original_numeric |
Optional. The original numeric/character vector of labels.
If not provided, it's inferred from |
Value
A list containing:
-
sample_score: A data frame withsample(ID),label(original numeric), andscore(predicted probability for positive class). -
evaluation_metrics: A list of performance metrics:-
Threshold_Strategy: The strategy used for threshold selection. -
_Threshold: The chosen probability threshold. -
Accuracy,Precision,Recall,F1,Specificity: Metrics calculated at_Threshold. -
AUROC: Area Under the Receiver Operating Characteristic curve. -
AUROC_95CI_Lower,AUROC_95CI_Upper: 95% confidence interval for AUROC. -
AUPRC: Area Under the Precision-Recall curve.
-
Examples
set.seed(42)
n_obs <- 50
X_toy <- data.frame(
FeatureA = rnorm(n_obs),
FeatureB = runif(n_obs, 0, 100)
)
y_toy <- factor(sample(c("Control", "Case"), n_obs, replace = TRUE),
levels = c("Control", "Case"))
ids_toy <- paste0("Sample", 1:n_obs)
# 2. Train a model
rf_model <- rf_dia(X_toy, y_toy)
# 3. Evaluate the model using F1-score optimal threshold
eval_results <- evaluate_model_dia(
model_obj = rf_model,
X_data = X_toy,
y_data = y_toy,
sample_ids = ids_toy,
threshold_choices = "f1",
pos_class = "Case",
neg_class = "Control"
)
str(eval_results)
Evaluate Prognostic Model Performance
Description
Comprehensive evaluation of survival models using:
Harrell's Concordance Index (C-index).
Time-dependent Area Under the ROC Curve (AUROC) at specified years.
Kaplan-Meier analysis comparing high vs. low risk groups (based on median split).
Usage
evaluate_model_pro(
trained_model_obj = NULL,
X_data = NULL,
Y_surv_obj,
sample_ids,
years_to_evaluate = c(1, 3, 5),
precomputed_score = NULL,
meta_normalize_params = NULL
)
Arguments
trained_model_obj |
A trained model object (optional if precomputed_score provided). |
X_data |
Features for prediction (optional if precomputed_score provided). |
Y_surv_obj |
True survival object. |
sample_ids |
Vector of IDs. |
years_to_evaluate |
Numeric vector of years for time-dependent AUC. |
precomputed_score |
Numeric vector of pre-calculated risk scores. |
meta_normalize_params |
Internal use. |
Value
A list containing a dataframe of scores and a list of evaluation metrics.
Evaluate Predictions from a Data Frame
Description
Evaluates model performance from a data frame of predictions,
calculating metrics like AUROC, AUPRC, F1 score, etc. This function is designed
for use with prediction results, such as the output from apply_dia.
Usage
evaluate_predictions_dia(
prediction_df,
threshold_choices = "default",
pos_class = "Positive",
neg_class = "Negative"
)
Arguments
prediction_df |
A data frame containing predictions. Must contain
the columns |
threshold_choices |
A character string specifying the thresholding strategy ("default", "f1", "youden") or a numeric probability threshold value (0-1). |
pos_class |
A character string for the positive class label used in reporting.
Defaults to |
neg_class |
A character string for the negative class label used in reporting.
Defaults to |
Details
This function strictly requires the label column in prediction_df to adhere
to the following format:
-
1: Represents the positive class. -
0: Represents the negative class. -
NA: Will be ignored during calculation.
The function will stop with an error if any other values are found in the label column.
Value
A named list containing all calculated performance metrics.
Examples
# # Create a sample prediction data frame
# predictions_df <- data.frame(
# sample = 1:10,
# label = c(1, 0, 1, 1, 0, 0, 1, 0, 1, 0),
# score = c(0.9, 0.2, 0.8, 0.6, 0.3, 0.4, 0.95, 0.1, 0.7, 0.5)
# )
#
# # Evaluate the predictions using the 'f1' threshold strategy
# evaluation_results <- evaluate_predictions_dia(
# prediction_df = predictions_df,
# threshold_choices = "f1"
# )
#
# print(evaluation_results)
Evaluate External Predictions
Description
Calculates performance metrics for external prediction sets.
Usage
evaluate_predictions_pro(prediction_df, years_to_evaluate = c(1, 3, 5))
Arguments
prediction_df |
Data frame with columns |
years_to_evaluate |
Years for AUC. |
Value
List of evaluation metrics.
Plot Diagnostic Model Evaluation Figures
Description
Generates and returns a ggplot object for Receiver Operating Characteristic (ROC) curves, Precision-Recall (PRC) curves, or confusion matrices.
Usage
figure_dia(type, data, file = NULL)
Arguments
type |
String, specifies the type of plot to generate. Options are "roc", "prc", or "matrix". |
data |
A list object containing model evaluation results. It must include:
|
file |
Optional. A string specifying the path to save the plot (e.g.,
"plot.png"). If |
Value
A ggplot object. If the file argument is provided, the plot is also
saved to the specified path.
Examples
# Create example data for a diagnostic model
external_eval_example_dia <- list(
sample_score = data.frame(
ID = paste0("S", 1:100),
label = sample(c(0, 1), 100, replace = TRUE),
score = runif(100, 0, 1)
),
evaluation_metrics = list(
Final_Threshold = 0.53
)
)
# Generate an ROC curve plot object
roc_plot <- figure_dia(type = "roc", data = external_eval_example_dia)
# To display the plot, simply run:
# print(roc_plot)
# Generate a PRC curve and save it to a temporary file
# tempfile() creates a safe, temporary path as required by CRAN
temp_prc_path <- tempfile(fileext = ".png")
figure_dia(type = "prc", data = external_eval_example_dia, file = temp_prc_path)
# Generate a Confusion Matrix plot
matrix_plot <- figure_dia(type = "matrix", data = external_eval_example_dia)
Plot Prognostic Model Evaluation Figures
Description
Generates and returns a ggplot object for Kaplan-Meier (KM) survival curves or time-dependent ROC curves.
Usage
figure_pro(type, data, file = NULL, time_unit = "days")
Arguments
type |
"km" or "tdroc" |
data |
list with:
|
file |
optional path to save |
time_unit |
"days" (default), "months", or "years" for df$time |
Value
ggplot object
Generate and Plot SHAP Explanation Figures
Description
Creates SHAP (SHapley Additive exPlanations) plots to explain feature contributions by training a surrogate model on the original model's scores.
Usage
figure_shap(data, raw_data, target_type, file = NULL, model_type = "xgboost")
Arguments
data |
A list containing |
raw_data |
A data frame with original features. The first column must be the sample ID. |
target_type |
String, the analysis type: "diagnosis" or "prognosis".
This determines which columns in |
file |
Optional. A string specifying the path to save the plot. If |
model_type |
String, the surrogate model for SHAP calculation. "xgboost" (default) or "lasso". |
Value
A patchwork object combining SHAP summary and importance plots. If file is
provided, the plot is also saved.
Examples
# --- Example for a Diagnosis Model ---
set.seed(123)
train_dia_data <- data.frame(
SampleID = paste0("S", 1:100),
Label = sample(c(0, 1), 100, replace = TRUE),
FeatureA = rnorm(100, 10, 2),
FeatureB = runif(100, 0, 5)
)
model_results <- list(
sample_score = data.frame(ID = paste0("S", 1:100), score = runif(100, 0, 1))
)
# Generate SHAP plot object
shap_plot <- figure_shap(
data = model_results,
raw_data = train_dia_data,
target_type = "diagnosis",
model_type = "xgboost"
)
# To display the plot:
# print(shap_plot)
Find Optimal Probability Threshold
Description
Determines an optimal probability threshold for binary classification based on maximizing F1-score or Youden's J statistic.
Usage
find_optimal_threshold_dia(
prob_positive,
y_true,
type = c("f1", "youden"),
pos_class,
neg_class
)
Arguments
prob_positive |
A numeric vector of predicted probabilities for the positive class. |
y_true |
A factor vector of true class labels. |
type |
A character string, specifying the optimization criterion: "f1" for F1-score or "youden" for Youden's J statistic (Sensitivity + Specificity - 1). |
pos_class |
A character string, the label for the positive class. |
neg_class |
A character string, the label for the negative class. |
Value
A numeric value, the optimal probability threshold.
Examples
y_true_ex <- factor(c("Negative", "Positive", "Positive", "Negative", "Positive"),
levels = c("Negative", "Positive"))
prob_ex <- c(0.1, 0.8, 0.6, 0.3, 0.9)
# Find threshold maximizing F1-score
opt_f1_threshold <- find_optimal_threshold_dia(
prob_positive = prob_ex,
y_true = y_true_ex,
type = "f1",
pos_class = "Positive",
neg_class = "Negative"
)
print(opt_f1_threshold)
# Find threshold maximizing Youden's J
opt_youden_threshold <- find_optimal_threshold_dia(
prob_positive = prob_ex,
y_true = y_true_ex,
type = "youden",
pos_class = "Positive",
neg_class = "Negative"
)
print(opt_youden_threshold)
Train a Gradient Boosting Machine (GBM) Model for Classification
Description
Trains a Gradient Boosting Machine (GBM) model using caret::train
for binary classification.
Usage
gbm_dia(X, y, tune = FALSE, cv_folds = 5, tune_length = 10)
Arguments
X |
A data frame of features. |
y |
A factor vector of class labels. |
tune |
Logical, whether to perform hyperparameter tuning for |
cv_folds |
An integer, the number of cross-validation folds for |
tune_length |
An integer, the number of random parameter combinations to try when tune=TRUE. Only used when search="random". Default is 20. |
Value
A caret::train object representing the trained GBM model.
Examples
set.seed(42)
n_obs <- 200
X_toy <- data.frame(
FeatureA = rnorm(n_obs),
FeatureB = runif(n_obs, 0, 100)
)
y_toy <- factor(sample(c("Control", "Case"), n_obs, replace = TRUE),
levels = c("Control", "Case"))
# Train the model with default parameters
gbm_model <- gbm_dia(X_toy, y_toy)
print(gbm_model)
# Train with extensive tuning (random search)
gbm_model_tuned <- gbm_dia(X_toy, y_toy, tune = TRUE, tune_length = 30)
print(gbm_model_tuned)
Train Gradient Boosting Machine (GBM) for Survival
Description
Fits a stochastic gradient boosting model using the Cox Partial Likelihood distribution. Supports random search for hyperparameter optimization.
Usage
gbm_pro(X, y_surv, tune = FALSE, cv.folds = 5, max_tune_iter = 10)
Arguments
X |
A data frame of predictors. |
y_surv |
A |
tune |
Logical. If TRUE, performs random search. |
cv.folds |
Integer. Number of cross-validation folds. |
max_tune_iter |
Integer. Maximum iterations for random search. |
Value
An object of class survival_gbm and pro_model.
Get Registered Diagnostic Models
Description
Retrieves a list of all diagnostic model functions currently registered in the internal environment.
Usage
get_registered_models_dia()
Value
A named list where names are the registered model names and values are the corresponding model functions.
See Also
register_model_dia, initialize_modeling_system_dia
Examples
# Ensure system is initialized to see the default models
initialize_modeling_system_dia()
models <- get_registered_models_dia()
# See available model names
print(names(models))
Get Registered Prognostic Models
Description
Retrieves the list of available models.
Usage
get_registered_models_pro()
Value
Named list of functions.
Train an EasyEnsemble Model for Imbalanced Classification
Description
Implements the EasyEnsemble algorithm. It trains multiple base models on balanced subsets of the data (by undersampling the majority class) and aggregates their predictions.
Usage
imbalance_dia(
data,
base_model_name = "xb",
n_estimators = 10,
tune_base_model = FALSE,
threshold_choices = "default",
positive_label_value = 1,
negative_label_value = 0,
new_positive_label = "Positive",
new_negative_label = "Negative",
seed = 456
)
Arguments
data |
A data frame where the first column is the sample ID, the second is the outcome label, and subsequent columns are features. |
base_model_name |
A character string, the name of the base diagnostic model to use (e.g., "xb", "rf"). This model must be registered. |
n_estimators |
An integer, the number of base models to train (number of subsets). |
tune_base_model |
Logical, whether to enable tuning for each base model. |
threshold_choices |
A character string (e.g., "f1", "youden", "default") or a numeric value (0-1) for determining the evaluation threshold for the ensemble. |
positive_label_value |
A numeric or character value in the raw data representing the positive class. |
negative_label_value |
A numeric or character value in the raw data representing the negative class. |
new_positive_label |
A character string, the desired factor level name for the positive class (e.g., "Positive"). |
new_negative_label |
A character string, the desired factor level name for the negative class (e.g., "Negative"). |
seed |
An integer, for reproducibility. |
Value
A list containing the model_object, sample_score, and evaluation_metrics.
See Also
initialize_modeling_system_dia, evaluate_model_dia
Examples
# 1. Initialize the modeling system
initialize_modeling_system_dia()
# 2. Create an imbalanced toy dataset
set.seed(42)
n_obs <- 100
n_minority <- 10
data_imbalanced_toy <- data.frame(
ID = paste0("Sample", 1:n_obs),
Status = c(rep(1, n_minority), rep(0, n_obs - n_minority)),
Feat1 = rnorm(n_obs),
Feat2 = runif(n_obs)
)
# 3. Run the EasyEnsemble algorithm
# n_estimators is reduced for a quick example
easyensemble_results <- imbalance_dia(
data = data_imbalanced_toy,
base_model_name = "xb",
n_estimators = 3,
threshold_choices = "f1"
)
print_model_summary_dia("EasyEnsemble (XGBoost)", easyensemble_results)
Initialize Diagnostic Modeling System
Description
Initializes the diagnostic modeling system by loading required
packages and registering default diagnostic models (Random Forest, XGBoost,
SVM, MLP, Lasso, Elastic Net, Ridge, LDA, QDA, Naive Bayes, Decision Tree, GBM).
This function should be called once before using models_dia() or ensemble methods.
Usage
initialize_modeling_system_dia()
Value
Invisible NULL. Initializes the internal model registry.
Examples
# Initialize the system (typically run once at the start of a session or script)
initialize_modeling_system_dia()
# Check if a default model like Random Forest is now registered
"rf" %in% names(get_registered_models_dia())
Initialize Prognosis Modeling System
Description
Initializes the environment and registers default survival models (Lasso, Elastic Net, Ridge, RSF, StepCox, GBM, XGBoost, PLS).
Usage
initialize_modeling_system_pro()
Comprehensive Diagnostic Modeling Pipeline
Description
Executes a complete diagnostic modeling workflow including single models, bagging, stacking, and voting ensembles across training and multiple test datasets. Returns structured results with AUROC values for visualization.
Usage
int_dia(
...,
model_names = NULL,
tune = TRUE,
n_estimators = 10,
seed = 123,
positive_label_value = 1,
negative_label_value = 0,
new_positive_label = "Positive",
new_negative_label = "Negative"
)
Arguments
... |
Data frames for analysis. The first is the training dataset; all subsequent arguments are test datasets. |
model_names |
Character vector specifying which models to use. If NULL (default), uses all registered models. |
tune |
Logical, enable hyperparameter tuning. Default TRUE. |
n_estimators |
Integer, number of bootstrap samples for bagging. Default 10. |
seed |
Integer for reproducibility. Default 123. |
positive_label_value |
Value representing positive class. Default 1. |
negative_label_value |
Value representing negative class. Default 0. |
new_positive_label |
Factor level name for positive class. Default "Positive". |
new_negative_label |
Factor level name for negative class. Default "Negative". |
Value
A list containing all_results, auroc_matrix, model_categories, dataset_names.
Imbalanced Data Diagnostic Modeling Pipeline
Description
Extends int_dia by adding imbalance-specific models (EasyEnsemble).
Produces a comprehensive set of models optimized for imbalanced datasets.
Usage
int_imbalance(
...,
model_names = NULL,
tune = TRUE,
n_estimators = 10,
seed = 123,
positive_label_value = 1,
negative_label_value = 0,
new_positive_label = "Positive",
new_negative_label = "Negative"
)
Arguments
... |
Data frames for analysis. The first is the training dataset; all subsequent arguments are test datasets. |
model_names |
Character vector specifying which models to use. If NULL (default), uses all registered models. |
tune |
Logical, enable hyperparameter tuning. Default TRUE. |
n_estimators |
Integer, number of bootstrap samples for bagging. Default 10. |
seed |
Integer for reproducibility. Default 123. |
positive_label_value |
Value representing positive class. Default 1. |
negative_label_value |
Value representing negative class. Default 0. |
new_positive_label |
Factor level name for positive class. Default "Positive". |
new_negative_label |
Factor level name for negative class. Default "Negative". |
Value
Same structure as int_dia with additional imbalance-handling models.
Examples
## Not run:
imbalanced_results <- int_imbalance(train_imbalanced, test_imbalanced)
## End(Not run)
Comprehensive Prognostic Modeling Pipeline
Description
Executes a complete prognostic (survival) modeling workflow including single models, bagging, and stacking ensembles. Returns C-index and time-dependent AUROC metrics.
Usage
int_pro(
...,
model_names = NULL,
tune = TRUE,
n_estimators = 10,
seed = 123,
time_unit = "day",
years_to_evaluate = c(1, 3, 5)
)
Arguments
... |
Data frames for survival analysis. First = training; others = test sets. Format: first column = ID, second = outcome (0/1), third = time, remaining = features. |
model_names |
Character vector specifying which models to use. If NULL (default), uses all registered prognostic models. |
tune |
Logical, enable tuning. Default TRUE. |
n_estimators |
Integer, bagging iterations. Default 10. |
seed |
Integer for reproducibility. Default 123. |
time_unit |
Time unit in data: "day", "month", or "year". Default "day". |
years_to_evaluate |
Numeric vector of years for time-dependent AUROC. Default c(1,3,5). |
Value
A list with:
-
all_results: All model outputs -
cindex_matrix: C-index values (models × datasets) -
avg_auroc_matrix: Average time-dependent AUROC (models × datasets) -
model_categories: Model category labels -
dataset_names: Dataset identifiers
Examples
## Not run:
prognosis_results <- int_pro(train_pro, test_pro1, test_pro2)
## End(Not run)
Train a Lasso (L1 Regularized Logistic Regression) Model for Classification
Description
Trains a Lasso-regularized logistic regression model using caret::train
(via glmnet method) for binary classification.
Usage
lasso_dia(X, y, tune = FALSE, cv_folds = 5)
Arguments
X |
A data frame of features. |
y |
A factor vector of class labels. |
tune |
Logical, whether to perform hyperparameter tuning for |
cv_folds |
An integer, the number of cross-validation folds for |
Value
A caret::train object representing the trained Lasso model.
Examples
set.seed(42)
n_obs <- 50
X_toy <- data.frame(
FeatureA = rnorm(n_obs),
FeatureB = runif(n_obs, 0, 100)
)
y_toy <- factor(sample(c("Control", "Case"), n_obs, replace = TRUE),
levels = c("Control", "Case"))
# Train the model
lasso_model <- lasso_dia(X_toy, y_toy)
print(lasso_model)
Train Lasso Cox Proportional Hazards Model
Description
Fits a Cox proportional hazards model regularized by the Lasso (L1) penalty. Uses cross-validation to select the optimal lambda.
Usage
lasso_pro(X, y_surv, tune = FALSE)
Arguments
X |
A data frame of predictors. |
y_surv |
A |
tune |
Logical. If TRUE, performs internal tuning (currently handled by cv.glmnet automatically). |
Value
An object of class survival_glmnet and pro_model.
Examples
library(survival)
# Create dummy data
set.seed(123)
df <- data.frame(time = rexp(50), status = sample(0:1, 50, replace=TRUE),
var1 = rnorm(50), var2 = rnorm(50))
y <- Surv(df$time, df$status)
x <- df[, c("var1", "var2")]
model <- lasso_pro(x, y)
print(class(model))
Train a Linear Discriminant Analysis (LDA) Model for Classification
Description
Trains a Linear Discriminant Analysis (LDA) model using caret::train
for binary classification.
Usage
lda_dia(X, y, tune = FALSE, cv_folds = 5)
Arguments
X |
A data frame of features. |
y |
A factor vector of class labels. |
tune |
Logical, whether to perform hyperparameter tuning (currently ignored for LDA). |
cv_folds |
An integer, the number of cross-validation folds for |
Value
A caret::train object representing the trained LDA model.
Examples
set.seed(42)
n_obs <- 50
X_toy <- data.frame(
FeatureA = rnorm(n_obs),
FeatureB = runif(n_obs, 0, 100)
)
y_toy <- factor(sample(c("Control", "Case"), n_obs, replace = TRUE),
levels = c("Control", "Case"))
# Train the model
lda_model <- lda_dia(X_toy, y_toy)
print(lda_model)
Load and Prepare Data for Diagnostic Models
Description
Loads a CSV file containing patient data, extracts features, and converts the label column into a factor suitable for classification models. Handles basic data cleaning like trimming whitespace and type conversion.
Usage
load_and_prepare_data_dia(
data_path,
label_col_name,
positive_label_value = 1,
negative_label_value = 0,
new_positive_label = "Positive",
new_negative_label = "Negative"
)
Arguments
data_path |
A character string, the file path to the input CSV data. The first column is assumed to be a sample ID. |
label_col_name |
A character string, the name of the column containing the class labels. |
positive_label_value |
A numeric or character value that represents the positive class in the raw data. |
negative_label_value |
A numeric or character value that represents the negative class in the raw data. |
new_positive_label |
A character string, the desired factor level name for the positive class (e.g., "Positive"). |
new_negative_label |
A character string, the desired factor level name for the negative class (e.g., "Negative"). |
Value
A list containing:
-
X: A data frame of features (all columns except ID and label). -
y: A factor vector of class labels, with levelsnew_negative_labelandnew_positive_label. -
sample_ids: A vector of sample IDs (the first column of the input data). -
pos_class_label: The character string used for the positive class factor level. -
neg_class_label: The character string used for the negative class factor level. -
y_original_numeric: The original numeric/character vector of labels.
Examples
# Create a dummy CSV file in a temporary directory for demonstration
temp_csv_path <- tempfile(fileext = ".csv")
dummy_data <- data.frame(
ID = paste0("Patient", 1:50),
Disease_Status = sample(c(0, 1), 50, replace = TRUE),
FeatureA = rnorm(50),
FeatureB = runif(50, 0, 100),
CategoricalFeature = sample(c("X", "Y", "Z"), 50, replace = TRUE)
)
write.csv(dummy_data, temp_csv_path, row.names = FALSE)
# Load and prepare data from the temporary file
prepared_data <- load_and_prepare_data_dia(
data_path = temp_csv_path,
label_col_name = "Disease_Status",
positive_label_value = 1,
negative_label_value = 0,
new_positive_label = "Case",
new_negative_label = "Control"
)
# Check prepared data structure
str(prepared_data$X)
table(prepared_data$y)
# Clean up the dummy file
unlink(temp_csv_path)
Min-Max Normalization
Description
Performs linear transformation of data to the range 0 to 1. Essential for stacking ensembles to normalize risk scores from heterogeneous base learners.
Usage
min_max_normalize(x, min_val = NULL, max_val = NULL)
Arguments
x |
A numeric vector. |
min_val |
Optional reference minimum value (e.g., from training set). |
max_val |
Optional reference maximum value (e.g., from training set). |
Value
A numeric vector of normalized values.
Train a Multi-Layer Perceptron (Neural Network) Model for Classification
Description
Trains a Multi-Layer Perceptron (MLP) neural network model
using caret::train for binary classification.
Usage
mlp_dia(X, y, tune = FALSE, cv_folds = 5)
Arguments
X |
A data frame of features. |
y |
A factor vector of class labels. |
tune |
Logical, whether to perform hyperparameter tuning using |
cv_folds |
An integer, the number of cross-validation folds for |
Value
A caret::train object representing the trained MLP model.
Examples
set.seed(42)
n_obs <- 50
X_toy <- data.frame(
FeatureA = rnorm(n_obs),
FeatureB = runif(n_obs, 0, 100)
)
y_toy <- factor(sample(c("Control", "Case"), n_obs, replace = TRUE),
levels = c("Control", "Case"))
# Train the model
mlp_model <- mlp_dia(X_toy, y_toy)
print(mlp_model)
Run Multiple Diagnostic Models
Description
Trains and evaluates one or more registered diagnostic models on a given dataset.
Usage
models_dia(
data,
model = "all_dia",
tune = FALSE,
seed = 123,
threshold_choices = "default",
positive_label_value = 1,
negative_label_value = 0,
new_positive_label = "Positive",
new_negative_label = "Negative"
)
Arguments
data |
A data frame where the first column is the sample ID, the second is the outcome label, and subsequent columns are features. |
model |
A character string or vector of character strings, specifying which models to run. Use "all_dia" to run all registered models. |
tune |
Logical, whether to enable hyperparameter tuning for individual models. |
seed |
An integer, for reproducibility of random processes. |
threshold_choices |
A character string (e.g., "f1", "youden", "default") or a numeric value (0-1), or a named list/vector allowing different threshold strategies/values for each model. |
positive_label_value |
A numeric or character value in the raw data representing the positive class. |
negative_label_value |
A numeric or character value in the raw data representing the negative class. |
new_positive_label |
A character string, the desired factor level name for the positive class (e.g., "Positive"). |
new_negative_label |
A character string, the desired factor level name for the negative class (e.g., "Negative"). |
Value
A named list, where each element corresponds to a run model and
contains its trained model_object, sample_score data frame, and
evaluation_metrics.
See Also
initialize_modeling_system_dia, evaluate_model_dia
Examples
# This example assumes your package includes a dataset named 'train_dia'.
# If not, you should create a toy data frame similar to the one below.
#
# train_dia <- data.frame(
# ID = paste0("Patient", 1:100),
# Disease_Status = sample(c(0, 1), 100, replace = TRUE),
# FeatureA = rnorm(100),
# FeatureB = runif(100)
# )
# Ensure the 'train_dia' dataset is available in the environment
# For example, if it is exported by your package:
# data(train_dia)
# Check if 'train_dia' exists, otherwise skip the example
if (exists("train_dia")) {
# 1. Initialize the modeling system
initialize_modeling_system_dia()
# 2. Run selected models
results <- models_dia(
data = train_dia,
model = c("rf", "lasso"), # Run only Random Forest and Lasso
threshold_choices = list(rf = "f1", lasso = 0.6), # Different thresholds
positive_label_value = 1,
negative_label_value = 0,
new_positive_label = "Case",
new_negative_label = "Control",
seed = 42
)
# 3. Print summaries
for (model_name in names(results)) {
print_model_summary_dia(model_name, results[[model_name]])
}
}
Run Multiple Prognostic Models
Description
High-level API to train and evaluate multiple survival models in batch.
Usage
models_pro(
data,
model = "all_pro",
tune = FALSE,
seed = 123,
time_unit = "day",
years_to_evaluate = c(1, 3, 5)
)
Arguments
data |
Input data frame. |
model |
Character vector of model names or "all_pro". |
tune |
Logical. Enable hyperparameter tuning? |
seed |
Random seed. |
time_unit |
Time unit of input. |
years_to_evaluate |
Years for AUC calculation. |
Value
A list of model results.
Train a Naive Bayes Model for Classification
Description
Trains a Naive Bayes model using caret::train for binary classification.
Usage
nb_dia(X, y, tune = FALSE, cv_folds = 5)
Arguments
X |
A data frame of features. |
y |
A factor vector of class labels. |
tune |
Logical, whether to perform hyperparameter tuning using |
cv_folds |
An integer, the number of cross-validation folds for |
Value
A caret::train object representing the trained Naive Bayes model.
Examples
set.seed(42)
n_obs <- 50
X_toy <- data.frame(
FeatureA = rnorm(n_obs),
FeatureB = runif(n_obs, 0, 100)
)
y_toy <- factor(sample(c("Control", "Case"), n_obs, replace = TRUE),
levels = c("Control", "Case"))
# Train the model
nb_model <- nb_dia(X_toy, y_toy)
print(nb_model)
Visualize Integrated Modeling Results
Description
Creates a heatmap visualization with performance metrics across models and datasets, including category annotations and summary bar plots.
Usage
plot_integrated_results(results_obj, metric_name = "AUROC", output_file = NULL)
Arguments
results_obj |
Output from |
metric_name |
Character string for metric used (e.g., "AUROC", "C-index"). |
output_file |
Optional file path to save plot. If NULL, plot is displayed. |
Value
A ggplot object (invisibly).
Examples
## Not run:
results <- int_dia(train_dia, test_dia)
plot_integrated_results(results, "AUROC")
## End(Not run)
Train Partial Least Squares Cox (PLS-Cox)
Description
Fits a Cox model using Partial Least Squares reduction for high-dimensional data.
Usage
pls_pro(X, y_surv, tune = FALSE)
Arguments
X |
A data frame of predictors. |
y_surv |
A |
tune |
Logical. If TRUE, performs internal tuning (currently handled by cv.glmnet automatically). |
Value
An object of class survival_plsRcox and pro_model.
Generic Prediction Interface for Prognostic Models
Description
A unified S3 generic method to generate prognostic risk scores from various trained model objects. This decouples the prediction implementation from the high-level evaluation logic, facilitating extensibility.
Usage
predict_pro(object, newdata, ...)
Arguments
object |
A trained model object with class |
newdata |
A data frame containing features for prediction. |
... |
Additional arguments passed to specific methods. |
Value
A numeric vector representing the prognostic risk score (higher values typically indicate higher risk).
Print Diagnostic Model Summary
Description
Prints a formatted summary of the evaluation metrics for a diagnostic model, either from training data or new data evaluation.
Usage
print_model_summary_dia(model_name, results_list, on_new_data = FALSE)
Arguments
model_name |
A character string, the name of the model (e.g., "rf", "Bagging (RF)"). |
results_list |
A list containing model evaluation results, typically
an element from the output of |
on_new_data |
Logical, indicating whether the results are from applying
the model to new, unseen data ( |
Value
NULL. Prints the summary to the console.
Examples
# Example for a successfully evaluated model
successful_results <- list(
evaluation_metrics = list(
Threshold_Strategy = "f1",
`_Threshold` = 0.45,
AUROC = 0.85, AUROC_95CI_Lower = 0.75, AUROC_95CI_Upper = 0.95,
AUPRC = 0.80, Accuracy = 0.82, F1 = 0.78,
Precision = 0.79, Recall = 0.77, Specificity = 0.85
)
)
print_model_summary_dia("MyAwesomeModel", successful_results)
# Example for a failed model
failed_results <- list(evaluation_metrics = list(error = "Training failed"))
print_model_summary_dia("MyFailedModel", failed_results)
Print Prognostic Model Summary
Description
Formatted console output of model performance.
Usage
print_model_summary_pro(model_name, results_list)
Arguments
model_name |
Name of the model. |
results_list |
Result object containing |
Train a Quadratic Discriminant Analysis (QDA) Model for Classification
Description
Trains a Quadratic Discriminant Analysis (QDA) model using caret::train
for binary classification.
Usage
qda_dia(X, y, tune = FALSE, cv_folds = 5)
Arguments
X |
A data frame of features. |
y |
A factor vector of class labels. |
tune |
Logical, whether to perform hyperparameter tuning (currently ignored for QDA). |
cv_folds |
An integer, the number of cross-validation folds for |
Value
A caret::train object representing the trained QDA model.
Examples
set.seed(42)
n_obs <- 50
X_toy <- data.frame(
FeatureA = rnorm(n_obs),
FeatureB = runif(n_obs, 0, 100)
)
y_toy <- factor(sample(c("Control", "Case"), n_obs, replace = TRUE),
levels = c("Control", "Case"))
# Train the model
qda_model <- qda_dia(X_toy, y_toy)
print(qda_model)
Register a Diagnostic Model Function
Description
Registers a user-defined or pre-defined diagnostic model function with the internal model registry. This allows the function to be called later by its registered name, facilitating a modular model management system.
Usage
register_model_dia(name, func)
Arguments
name |
A character string, the unique name to register the model under. |
func |
A function, the R function implementing the diagnostic model.
This function should typically accept |
Value
NULL. The function registers the model function invisibly.
See Also
get_registered_models_dia, initialize_modeling_system_dia
Examples
# Example of a dummy model function for registration
my_dummy_rf_model <- function(X, y, tune = FALSE, cv_folds = 5) {
message("Training dummy RF model...")
# This is a placeholder and doesn't train a real model.
# It returns a list with a structure similar to a caret train object.
list(method = "dummy_rf")
}
# Initialize the system before registering
initialize_modeling_system_dia()
# Register the new model
register_model_dia("dummy_rf", my_dummy_rf_model)
# Verify that the model is now in the list of registered models
"dummy_rf" %in% names(get_registered_models_dia())
Register a Prognostic Model
Description
Registers a model function into the internal system environment, making it available for batch execution.
Usage
register_model_pro(name, func)
Arguments
name |
String identifier for the model. |
func |
The model training function. |
Train a Random Forest Model for Classification
Description
Trains a Random Forest model using caret::train for binary classification.
Usage
rf_dia(X, y, tune = FALSE, cv_folds = 5)
Arguments
X |
A data frame of features. |
y |
A factor vector of class labels. |
tune |
Logical, whether to perform hyperparameter tuning using |
cv_folds |
An integer, the number of cross-validation folds for |
Value
A caret::train object representing the trained Random Forest model.
Examples
set.seed(42)
n_obs <- 50
X_toy <- data.frame(
FeatureA = rnorm(n_obs),
FeatureB = runif(n_obs, 0, 100)
)
y_toy <- factor(sample(c("Control", "Case"), n_obs, replace = TRUE),
levels = c("Control", "Case"))
# Train the model
rf_model <- rf_dia(X_toy, y_toy)
print(rf_model)
Train a Ridge (L2 Regularized Logistic Regression) Model for Classification
Description
Trains a Ridge-regularized logistic regression model using caret::train
(via glmnet method) for binary classification.
Usage
ridge_dia(X, y, tune = FALSE, cv_folds = 5)
Arguments
X |
A data frame of features. |
y |
A factor vector of class labels. |
tune |
Logical, whether to perform hyperparameter tuning for |
cv_folds |
An integer, the number of cross-validation folds for |
Value
A caret::train object representing the trained Ridge model.
Examples
set.seed(42)
n_obs <- 50
X_toy <- data.frame(
FeatureA = rnorm(n_obs),
FeatureB = runif(n_obs, 0, 100)
)
y_toy <- factor(sample(c("Control", "Case"), n_obs, replace = TRUE),
levels = c("Control", "Case"))
# Train the model
ridge_model <- ridge_dia(X_toy, y_toy)
print(ridge_model)
Train Ridge Cox Model
Description
Fits a Cox model with Ridge (L2) regularization.
Usage
ridge_pro(X, y_surv, tune = FALSE)
Arguments
X |
A data frame of predictors. |
y_surv |
A |
tune |
Logical. If TRUE, performs internal tuning (currently handled by cv.glmnet automatically). |
Value
An object of class survival_glmnet and pro_model.
Train Random Survival Forest (RSF)
Description
Fits a Random Survival Forest using the log-rank splitting rule.
Includes capabilities for hyperparameter tuning via grid search over ntree,
nodesize, and mtry.
Usage
rsf_pro(X, y_surv, tune = FALSE, tune_params = NULL)
Arguments
X |
A data frame of predictors. |
y_surv |
A |
tune |
Logical. If TRUE, performs grid search for optimal hyperparameters based on C-index. |
tune_params |
Optional data frame containing the grid for tuning. |
Value
An object of class survival_rsf and pro_model.
Train a Stacking Diagnostic Model
Description
Implements a Stacking ensemble. It trains multiple base models, then uses their predictions as features to train a meta-model.
Usage
stacking_dia(
results_all_models,
data,
meta_model_name,
top = 5,
tune_meta = FALSE,
threshold_choices = "f1",
seed = 789,
positive_label_value = 1,
negative_label_value = 0,
new_positive_label = "Positive",
new_negative_label = "Negative"
)
Arguments
results_all_models |
A list of results from |
data |
A data frame where the first column is the sample ID, the second is the outcome label, and subsequent columns are features. Used for training the meta-model. |
meta_model_name |
A character string, the name of the meta-model to use (e.g., "lasso", "gbm"). This model must be registered. |
top |
An integer, the number of top-performing base models (ranked by AUROC) to select for the stacking ensemble. |
tune_meta |
Logical, whether to enable tuning for the meta-model. |
threshold_choices |
A character string (e.g., "f1", "youden", "default") or a numeric value (0-1) for determining the evaluation threshold for the ensemble. |
seed |
An integer, for reproducibility. |
positive_label_value |
A numeric or character value in the raw data representing the positive class. |
negative_label_value |
A numeric or character value in the raw data representing the negative class. |
new_positive_label |
A character string, the desired factor level name for the positive class (e.g., "Positive"). |
new_negative_label |
A character string, the desired factor level name for the negative class (e.g., "Negative"). |
Value
A list containing the model_object, sample_score, and evaluation_metrics.
See Also
models_dia, evaluate_model_dia
Examples
# 1. Initialize the modeling system
initialize_modeling_system_dia()
# 2. Create a toy dataset for demonstration
set.seed(42)
data_toy <- data.frame(
ID = paste0("Sample", 1:60),
Status = sample(c(0, 1), 60, replace = TRUE),
Feat1 = rnorm(60),
Feat2 = runif(60)
)
# 3. Generate mock base model results (as if from models_dia)
# In a real scenario, you would run models_dia() on your full dataset
base_model_results <- models_dia(
data = data_toy,
model = c("rf", "lasso"),
seed = 123
)
# 4. Run the stacking ensemble
stacking_results <- stacking_dia(
results_all_models = base_model_results,
data = data_toy,
meta_model_name = "gbm",
top = 2,
threshold_choices = "f1"
)
print_model_summary_dia("Stacking (GBM)", stacking_results)
Train Stacking Ensemble for Prognosis
Description
Implements a Stacking Ensemble (Super Learner). It uses the risk scores from top-performing base models as meta-features to train a second-level meta-learner.
Usage
stacking_pro(
results_all_models,
data,
meta_model_name,
top = 3,
tune_meta = FALSE,
time_unit = "day",
years_to_evaluate = c(1, 3, 5),
seed = 789
)
Arguments
results_all_models |
List of results from |
data |
Training data. |
meta_model_name |
Name of the meta-learner (e.g., "lasso_pro"). |
top |
Integer. Number of top base models to include based on C-index. |
tune_meta |
Logical. Tune the meta-learner? |
time_unit |
Time unit. |
years_to_evaluate |
Evaluation years. |
seed |
Integer seed. |
Value
A list containing the stacking object and evaluation results.
Train Stepwise Cox Model (AIC-based)
Description
Fits a Cox model and performs backward stepwise selection based on AIC.
Usage
stepcox_pro(X, y_surv, tune = FALSE)
Arguments
X |
A data frame of predictors. |
y_surv |
A |
tune |
Logical. If TRUE, performs internal tuning (currently handled by cv.glmnet automatically). |
Value
An object of class survival_stepcox and pro_model.
Train a Support Vector Machine (Linear Kernel) Model for Classification
Description
Trains a Support Vector Machine (SVM) model with a linear kernel
using caret::train for binary classification.
Usage
svm_dia(X, y, tune = FALSE, cv_folds = 5)
Arguments
X |
A data frame of features. |
y |
A factor vector of class labels. |
tune |
Logical, whether to perform hyperparameter tuning using |
cv_folds |
An integer, the number of cross-validation folds for |
Value
A caret::train object representing the trained SVM model.
Examples
set.seed(42)
n_obs <- 50
X_toy <- data.frame(
FeatureA = rnorm(n_obs),
FeatureB = runif(n_obs, 0, 100)
)
y_toy <- factor(sample(c("Control", "Case"), n_obs, replace = TRUE),
levels = c("Control", "Case"))
# Train the model
svm_model <- svm_dia(X_toy, y_toy)
print(svm_model)
Test Data for Diagnostic Models
Description
A test dataset for evaluating diagnostic models, with a structure
identical to train_dia.
Usage
test_dia
Format
A data frame with rows for samples and 22 columns:
- sample
character. Unique identifier for each sample.
- outcome
integer. The binary outcome (0 or 1).
- AC004637.1
numeric. Gene expression level.
- AC008459.1
numeric. Gene expression level.
- AC009242.1
numeric. Gene expression level.
- AC016735.1
numeric. Gene expression level.
- AC090125.1
numeric. Gene expression level.
- AC104237.3
numeric. Gene expression level.
- AC112721.2
numeric. Gene expression level.
- AC246817.1
numeric. Gene expression level.
- AL135841.1
numeric. Gene expression level.
- AL139241.1
numeric. Gene expression level.
- HYMAI
numeric. Gene expression level.
- KCNIP2.AS1
numeric. Gene expression level.
- LINC00639
numeric. Gene expression level.
- LINC00922
numeric. Gene expression level.
- LINC00924
numeric. Gene expression level.
- LINC00958
numeric. Gene expression level.
- LINC01028
numeric. Gene expression level.
- LINC01614
numeric. Gene expression level.
- LINC01644
numeric. Gene expression level.
- PRDM16.DT
numeric. Gene expression level.
Source
Stored in data/test_dia.rda.
Test Data for Prognostic (Survival) Models
Description
A test dataset for evaluating prognostic models, with a structure
identical to train_pro.
Usage
test_pro
Format
A data frame with rows for samples and 31 columns:
- sample
character. Unique identifier for each sample.
- outcome
integer. The event status (0 or 1).
- time
numeric. The time to event or censoring.
- AC004990.1
numeric. Gene expression level.
- AC055854.1
numeric. Gene expression level.
- AC084212.1
numeric. Gene expression level.
- AC092118.1
numeric. Gene expression level.
- AC093515.1
numeric. Gene expression level.
- AC104211.1
numeric. Gene expression level.
- AC105046.1
numeric. Gene expression level.
- AC105219.1
numeric. Gene expression level.
- AC110772.2
numeric. Gene expression level.
- AC133644.1
numeric. Gene expression level.
- AL133467.1
numeric. Gene expression level.
- AL391845.2
numeric. Gene expression level.
- AL590434.1
numeric. Gene expression level.
- AL603840.1
numeric. Gene expression level.
- AP000851.2
numeric. Gene expression level.
- AP001434.1
numeric. Gene expression level.
- C9orf163
numeric. Gene expression level.
- FAM153CP
numeric. Gene expression level.
- HOTAIR
numeric. Gene expression level.
- HYMAI
numeric. Gene expression level.
- LINC00165
numeric. Gene expression level.
- LINC01028
numeric. Gene expression level.
- LINC01152
numeric. Gene expression level.
- LINC01497
numeric. Gene expression level.
- LINC01614
numeric. Gene expression level.
- LINC01929
numeric. Gene expression level.
- LINC02408
numeric. Gene expression level.
- SIRLNT
numeric. Gene expression level.
Source
Stored in data/test_pro.rda.
Training Data for Diagnostic Models
Description
A training dataset for diagnostic models, containing sample IDs, binary outcomes, and gene expression features.
Usage
train_dia
Format
A data frame with rows for samples and 22 columns:
- sample
character. Unique identifier for each sample.
- outcome
integer. The binary outcome, where 1 typically represents a positive case and 0 a negative case.
- AC004637.1
numeric. Gene expression level.
- AC008459.1
numeric. Gene expression level.
- AC009242.1
numeric. Gene expression level.
- AC016735.1
numeric. Gene expression level.
- AC090125.1
numeric. Gene expression level.
- AC104237.3
numeric. Gene expression level.
- AC112721.2
numeric. Gene expression level.
- AC246817.1
numeric. Gene expression level.
- AL135841.1
numeric. Gene expression level.
- AL139241.1
numeric. Gene expression level.
- HYMAI
numeric. Gene expression level.
- KCNIP2.AS1
numeric. Gene expression level.
- LINC00639
numeric. Gene expression level.
- LINC00922
numeric. Gene expression level.
- LINC00924
numeric. Gene expression level.
- LINC00958
numeric. Gene expression level.
- LINC01028
numeric. Gene expression level.
- LINC01614
numeric. Gene expression level.
- LINC01644
numeric. Gene expression level.
- PRDM16.DT
numeric. Gene expression level.
Details
This dataset is used to train machine learning models for diagnosis. The column names starting with 'AC', 'AL', 'LINC', etc., are feature variables.
Source
Stored in data/train_dia.rda.
Training Data for Prognostic (Survival) Models
Description
A training dataset for prognostic models, containing sample IDs, survival outcomes (time and event status), and gene expression features.
Usage
train_pro
Format
A data frame with rows for samples and 31 columns:
- sample
character. Unique identifier for each sample.
- outcome
integer. The event status, where 1 indicates an event occurred and 0 indicates censoring.
- time
numeric. The time to event or censoring.
- AC004990.1
numeric. Gene expression level.
- AC055854.1
numeric. Gene expression level.
- AC084212.1
numeric. Gene expression level.
- AC092118.1
numeric. Gene expression level.
- AC093515.1
numeric. Gene expression level.
- AC104211.1
numeric. Gene expression level.
- AC105046.1
numeric. Gene expression level.
- AC105219.1
numeric. Gene expression level.
- AC110772.2
numeric. Gene expression level.
- AC133644.1
numeric. Gene expression level.
- AL133467.1
numeric. Gene expression level.
- AL391845.2
numeric. Gene expression level.
- AL590434.1
numeric. Gene expression level.
- AL603840.1
numeric. Gene expression level.
- AP000851.2
numeric. Gene expression level.
- AP001434.1
numeric. Gene expression level.
- C9orf163
numeric. Gene expression level.
- FAM153CP
numeric. Gene expression level.
- HOTAIR
numeric. Gene expression level.
- HYMAI
numeric. Gene expression level.
- LINC00165
numeric. Gene expression level.
- LINC01028
numeric. Gene expression level.
- LINC01152
numeric. Gene expression level.
- LINC01497
numeric. Gene expression level.
- LINC01614
numeric. Gene expression level.
- LINC01929
numeric. Gene expression level.
- LINC02408
numeric. Gene expression level.
- SIRLNT
numeric. Gene expression level.
Details
This dataset is used to train machine learning models for prognosis. The features are typically gene expression values.
Source
Stored in data/train_pro.rda.
Train a Voting Ensemble Diagnostic Model
Description
Implements a Voting ensemble, combining predictions from multiple base models through soft or hard voting.
Usage
voting_dia(
results_all_models,
data,
type = c("soft", "hard"),
weight_metric = "AUROC",
top = 5,
seed = 789,
threshold_choices = "f1",
positive_label_value = 1,
negative_label_value = 0,
new_positive_label = "Positive",
new_negative_label = "Negative"
)
Arguments
results_all_models |
A list of results from |
data |
A data frame where the first column is the sample ID, the second is the outcome label, and subsequent columns are features. Used for evaluation. |
type |
A character string, "soft" for weighted average of probabilities or "hard" for majority class voting. |
weight_metric |
A character string, the metric to use for weighting base models in soft voting (e.g., "AUROC", "F1"). Ignored for hard voting. |
top |
An integer, the number of top-performing base models (ranked by
|
seed |
An integer, for reproducibility. |
threshold_choices |
A character string (e.g., "f1", "youden", "default") or a numeric value (0-1) for determining the evaluation threshold for the ensemble. |
positive_label_value |
A numeric or character value in the raw data representing the positive class. |
negative_label_value |
A numeric or character value in the raw data representing the negative class. |
new_positive_label |
A character string, the desired factor level name for the positive class (e.g., "Positive"). |
new_negative_label |
A character string, the desired factor level name for the negative class (e.g., "Negative"). |
Value
A list containing the model_object, sample_score, and evaluation_metrics.
See Also
models_dia, evaluate_model_dia
Examples
# 1. Initialize the modeling system
initialize_modeling_system_dia()
# 2. Create a toy dataset for demonstration
set.seed(42)
data_toy <- data.frame(
ID = paste0("Sample", 1:60),
Status = sample(c(0, 1), 60, replace = TRUE),
Feat1 = rnorm(60),
Feat2 = runif(60)
)
# 3. Generate mock base model results (as if from models_dia)
base_model_results <- models_dia(
data = data_toy,
model = c("rf", "lasso"),
seed = 123
)
# 4. Run the soft voting ensemble
soft_voting_results <- voting_dia(
results_all_models = base_model_results,
data = data_toy,
type = "soft",
weight_metric = "AUROC",
top = 2,
threshold_choices = "f1"
)
print_model_summary_dia("Soft Voting", soft_voting_results)
Train an XGBoost Tree Model for Classification
Description
Trains an Extreme Gradient Boosting (XGBoost) model using caret::train
for binary classification.
Usage
xb_dia(X, y, tune = FALSE, cv_folds = 5, tune_length = 20)
Arguments
X |
A data frame of features. |
y |
A factor vector of class labels. |
tune |
Logical, whether to perform hyperparameter tuning using |
cv_folds |
An integer, the number of cross-validation folds for |
tune_length |
An integer, the number of random parameter combinations to try when tune=TRUE. Only used when search="random". Default is 20. |
Value
A caret::train object representing the trained XGBoost model.
Examples
set.seed(42)
n_obs <- 50
X_toy <- data.frame(
FeatureA = rnorm(n_obs),
FeatureB = runif(n_obs, 0, 100)
)
y_toy <- factor(sample(c("Control", "Case"), n_obs, replace = TRUE),
levels = c("Control", "Case"))
# Train the model
xb_model <- xb_dia(X_toy, y_toy)
print(xb_model)
Train XGBoost Cox Model
Description
Fits an XGBoost model using the Cox proportional hazards objective function.
Usage
xgb_pro(X, y_surv, tune = FALSE)
Arguments
X |
A data frame of predictors. |
y_surv |
A |
tune |
Logical. If TRUE, performs internal tuning (currently handled by cv.glmnet automatically). |
Value
An object of class survival_xgboost and pro_model.