NEWS

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exposureEM 0.3.0 (2026-09-21)

• All three component links (cloglog, logit, and log) now support EM, direct Marquardt Newton-Raphson, and hybrid fitting.
• Added analytic observed-likelihood derivatives for logit and log. The hybrid uses the chosen link throughout, and final inference uses its unmodified observed Hessian. Log-link proposals outside the probability domain are rejected by backtracking. No new dependencies or public controls were added.
• Scaled the direct line-search rounding allowance to the summed likelihood to prevent false failures near a root on large samples.
• Expanded derivative, EM/direct/hybrid agreement, covariance, rare-probability, and domain-backtracking tests; updated examples and algorithm documentation.
• Version 0.2.0 Win-builder results do not validate this extension. Repeat R-release and R-devel checks on the 0.3.0 archive before submission.

exposureEM 0.2.0

• Added direct observed-likelihood Marquardt Newton-Raphson and EM-initialized hybrid fitting through exposure_fit(). Pure EM remains available through exposure_em(); no ES algorithm is included.
• Verified all three EM component links, their full Newton M-steps, Louis information, and the cloglog observed derivatives against independent numerical differentiation and likelihood optimization.
• EM termination now checks observed likelihood change and the unmodified score-curvature measure as well as the selected change criterion. Direct termination consistently applies the three change and curvature checks. Final observed scores and Newton decrements are returned for all methods.
• Reject indefinite covariance information and constant cloglog exposure proportions. Validate integer limits, named controls, logical settings, finite covariates, response shape, and unsupported formula offsets.
• Stabilized structural-zero exposure calculations and rare-event direct derivatives. The EM Q ascent check now allows rounding error proportional to objective size; tiny M-step changes also require a small score.
• Fixed missing-exposure prediction for logit, domain checking with mixed missing and invalid predictions, and na.exclude restoration in standard prediction, fitted-value, and residual methods.
• Hybrid warm-up is documented as an upper iteration limit and respects each phase's trace setting. Documentation now explains inference assumptions, convergence limitations, returned fields, and the absence of a proven hybrid runtime advantage.
• Added self-contained numerical safeguard tests. The restricted-data ABCD comparison remains in the local source tree but is excluded from source archives; the installed smoke-test example is portable.