Package: fdb Type: Package Title: Frequentist Dynamic Borrowing for Hybrid-Control Survival Trials Version: 0.2.2 Authors@R: person(given = "Yusuke", family = "Yamaguchi", role = c("aut", "cre"), email = "yamagubed@gmail.com") Description: Implements a class of likelihood-informed frequentist dynamic borrowing methods for hybrid-control survival trials based on penalized Cox partial likelihood estimation. Implements four likelihood-informed penalty structures (precision-weighted L1, smoothed integrated-gate, information-adaptive minimax concave penalty (MCP), and likelihood-ratio-weighted L1), together with the adaptive lasso borrowing approach of Li et al. (2023, ). Provides conditional model-based standard errors and local plug-in sandwich variance approximations, with smoothed penalties. Tools for design-stage lambda calibration via simulation, including a two-stage coarse-fine grid search, drift-level early stopping, and per-method tuning under both inference types, are also provided. A simulation harness for evaluating type I error and statistical power across population drift scenarios is included. License: MIT + file LICENSE Encoding: UTF-8 Depends: R (>= 3.6.0) Imports: survival, stats, parallel, utils Suggests: testthat (>= 3.0.0), knitr, rmarkdown VignetteBuilder: knitr URL: https://github.com/yamagubed/fdb BugReports: https://github.com/yamagubed/fdb/issues Config/testthat/edition: 3 Config/roxygen2/version: 8.1.0 RoxygenNote: 7.3.3 Repository: https://yamagubed.r-universe.dev Date/Publication: 2026-10-09 16:53:10 UTC RemoteUrl: https://github.com/yamagubed/fdb RemoteRef: HEAD RemoteSha: dbbb2acd9744b01192beaede971dc8c81dc8d916 NeedsCompilation: no Packaged: 2026-10-09 21:19:36 UTC; root Author: Yusuke Yamaguchi [aut, cre] Maintainer: Yusuke Yamaguchi