DEmixR

• **L-BFGS-B convergence is checked.** A local refinement is accepted only if optim() reports convergence code 0. Otherwise a warning is given and the unrefined DE solution is returned (fit$source == "DEoptim_nolocal"). fit$convergence and fit$message now describe the returned candidate (0.2.0 always reported the run started from the DE solution).
• **Defaults of n_runs.** fit_norm2(), fit_lognorm2() now default to n_runs = 10 (was 20). select_best_mixture() now uses the same defaults as the fitting functions, n_runs = 10, NP = 100 (was 1 and 50).
• **Bootstrap.** Replicates are accepted only if the refinement converged; default bounds are recomputed from every bootstrap sample (as for the original fit); central is now the **median for both families** (0.2.0: mean for normal, median for lognormal; use center = "mean"); the mean and median are always returned.
• **P-P plot.** The "pp" panel of prelim_plots() is now a proper normal P-P plot. In 0.2.0 it plotted the sorted empirical-CDF values against the observation index, which is the same straight line for any data set.

New features

• mix2_bounds() (exported) returns the data-derived parameter bounds; the scale limits and the range of the mixing proportion are controlled with scale_range and p_range. The bounds are documented: the mean bounds are *not* split at the median.
• Input validation: x must be finite (no NA/NaN/Inf) with at least 10 observations and non-zero variance; a warning is given for n < 50; user bounds must have length 5, be finite and ordered, and stay inside the model.
• Fit objects store source, local_convergence, the bounds (lower, upper), settings, de_logLik (log-likelihood of each DE run) and diagnostics. Warnings and print()/summary() notes flag solutions on a bound of the parameter box and components whose expected size (sum of posterior probabilities) is below min_comp_n (default 5).
• scale_ratio argument (default 0 = off): a Hathaway (1985)-type relative constraint min(s1, s2) / max(s1, s2) >= scale_ratio, enforced by a quadratic penalty; the reported log-likelihood is the exact one. It is inherited by bootstrap_mix2() from the fit.
• bootstrap_mix2(refit = "de") repeats a differential-evolution search for every replicate (de_control); refit = "local" (default) is the fast local refit of 0.2.0 and is documented as not propagating multimodality. Failed replicates are counted (n_failed).
• plot(fit, which = "pit") and which = "qq" compare the data with the fitted mixture. prelim_plots() gains "logpp".
• select_best_mixture(criterion = "BIC" | "AIC"); errors of an individual family fit are reported instead of being swallowed.

Bug fixes and documentation

• parallelType = 1 requires the parallelly package because DEoptim does; it is listed under Suggests and a clear error is given if missing. The parallel objective is now self-contained for PSOCK workers, so internal DEmixR functions are not required on the worker search path. The numerical objective and the meanings of parallelType are unchanged. DEoptim uses 0 = serial, 1 = parallel, and 2 = foreach.
• In bootstrap_mix2(), parallelType is the number of forked processes (values 0 and 1 run serially; ignored on Windows); the documentation of 0.2.0 described it as the DEoptim setting.
• Documentation states that the search is bounded and that the result is not an unrestricted maximum-likelihood estimate; the lognormal m/s are meanlog/sdlog; Q-Q/P-P panels are exploratory.
• Test suite extended (validation, likelihood, boundary diagnostics, non-convergence handling, bootstrap failure handling, reproducibility).