Electronics, Journal Year: 2025, Volume and Issue: 14(9), P. 1838 - 1838
Published: April 30, 2025
Probability calibration and decision threshold selection are fundamental aspects of risk prediction classification, respectively. A strictly proper loss function is used in clinical applications to encourage a model predict calibrated class-posterior probabilities or risks. Recent studies have shown that training with focal can improve the discriminatory power gradient-boosted trees (GBDT) for classification tasks an imbalanced skewed class distribution. However, not function. Therefore, output GBDT trained using accurate estimate true probability. This study aims address issue poor context applications. The methodology utilizes closed-form transformation confidence scores relates minimizer true-class posterior Algorithms based on Bayesian hyperparameter optimization provided choose parameter optimizes calibration, as measured by Brier score metric. We assess how affects optimize balanced accuracy, defined arithmetic mean sensitivity specificity. effectiveness proposed strategy was evaluated lung transplant data extracted from Scientific Registry Transplant Recipients (SRTR) predicting post-transplant cancer. also Behavioral Risk Factor Surveillance System (BRFSS) diabetes status. plots, slope intercept, show approach improves while maintaining same according area under receiver operating characteristics curve (AUROC) H-measure. focal-aware XGBoost achieved AUROC, score, 0.700, 0.128, 0.968 10-year cancer risk, miscalibrated equal AUROC but worse (0.140 1.579). method compared favorably standard cross-entropy (AUROC 0.755 versus 0.736 1-year cancer). Comparable performance observed other models task.
Language: Английский