Changes for version 0.27 - 2026-07-26
- New `h` function: `h('agg')`, `h(*agg)` or `h(\&agg)` prints that function's section of this document and returns, in the spirit of R's `?function`. `h()` lists every documented function. It covers the XS functions as well as the Perl ones, because it looks the name up in the module's POD instead of reading an argument list — see [Getting help](#getting-help).
- The pure Perl functions also accept `'?'` or `'h'` in place of their arguments, which prints the same text and then dies. `$Stats::LikeR::HELP = 0` switches that off for code that has to pass a column or file really named `'h'`.
- `qcut`'s hand-written usage message was replaced by its section of this document; `qcut('h')` and `qcut('?')` still die, but `qcut('H')` no longer means help.
- speed improvements in calculation of Kendall tau and p-value. Improvement of writing xlsx files that won't show in time, but pure waste was removed.
- Addition of `auc`, `auroc`, `cmh_test`, `epi_2x2`, `roc` functions
- `prcomp` now accepts AoH input
- glm extended (LikeR.xs)
- family => 'poisson' (log link) and family => 'negbin' — negative-binomial θ estimated by ML via a MASS::glm.nb-style outer loop, or fixed with theta =>. Matched R to ~1e-8 (coefs, deviance, null-dev, AIC, SE, θ); exact Poisson limit when data aren't over-dispersed.
- Every non-gaussian family now returns exp (odds/rate/incidence-rate ratios + conf.low/conf.high), link-scale conf.int, conf.level, and theta (negbin). Count families report z-statistics. OR/CI matched R's confint.default exactly.
- New XS tests (all matched R exactly)
- prop_test — 1/2/k-sample proportions (Yates, Wilson & Wald-diff CIs)
- mcnemar_test — matrix or paired vectors; continuity correction; exact => 1 binomial
- friedman_test — repeated-measures rank test, tie-corrected
- dunn_test — post-Kruskal pairwise, 7 adjustment methods
- New Perl functions (lib/Stats/LikeR.pm, matched base-R references)
- Effect sizes: cohen_d (+Hedges g, CI), smd, cramers_v (+Bergsma bias-corrected), eta_squared (η²/partial/ω²)
- vif, hosmer_lemeshow (matches hoslem.test)
- age_standardize — direct standardization + Fay–Feuer gamma CI (matches epitools::ageadjust.direct)
Modules
Get basic statistical functions, like in R, but with Perl using XS for performance
Provides
in lib/Stats/LikeR.pm