Statistical Results in APA Style

Proper formatting of statistical results in accordance with the American Psychological Association (APA) Manual (sixth edition), along with convenient helpers for summaries, confidence intervals, and plotting. Development repository: < https://github.com/achetverikov/APAstats>.

apastats2

Utilities for APA-style reporting of statistical results, plus helper functions for confidence intervals, summaries, and plotting.

Install

install.packages("remotes")
remotes::install_github("achetverikov/apastats")

Quick Example

library(apastats2)

t_res <- t.test(rnorm(20, mean = 10, sd = 2))
apa(t_res)

Example Output

How the results look when the Markdown strings are rendered in R Markdown or Quarto:

Source: example/readme_output.Rmd (built-in R datasets).

Main Function Families

• apa(): formatted output for many model/test objects via S3 methods
• apa_*: APA-formatted means, confidence intervals, test statistics
• get_adjusted_ci(): confidence intervals/SEs for between-subject, within-subject, and mixed designs
• plot_pointrange(): point-range plotting using the same adjusted-interval engine
• misc utilities (round_p(), f_round(), drop_empty_cols(), etc.)

Documentation

• Website: https://achetverikov.github.io/APAstats/
• Function help: ?apa, ?apa_mean_conf, etc.
• Vignette: vignette("apastats2-intro", package = "apastats2")

Notes

Some advanced methods rely on suggested packages (for example ez, lme4, and emmeans).

Transition from apastats to apastats2

If you are migrating old scripts:

1. Install/load the new package:

remotes::install_github("achetverikov/apastats")
library(apastats2)

1. Prefer apa() and apa_* functions in new code.
2. Legacy describe.* functions still work for now, but are deprecated and planned for removal.
3. Legacy dot-named utility functions are also deprecated; use snake_case equivalents (see mapping below).

In most cases, replacing library(apastats) with library(apastats2) and then progressively updating deprecated calls is enough.

Deprecated Mappings

Legacy describe.* wrappers are deprecated and will be removed in the next release. Use the following replacements:

• describe.ttest() -> apa() (for t.test objects)
• describe.r() -> apa() (for cor.test objects)
• describe.chi() -> apa() (for chisq.test objects)
• describe.glm() -> apa() (for glm/lm objects)
• describe.mean.sd() -> apa_mean_sd()
• describe.mean.conf() -> apa_mean_conf()
• describe.binom.mean.conf() -> apa_binom_mean_conf()
• describe.mean.and.t() -> apa_mean_and_t()

Additional deprecated compatibility mapping:

• get_superb_ci() -> get_adjusted_ci()

For utility helpers, snake_case aliases are now available and dot-named forms are legacy:

• mean.nn() -> mean_nn()
• sd.nn() -> sd_nn()
• sum.nn() -> sum_nn()
• drop.empty.cols() -> drop_empty_cols()
• binom.ci() -> binom_ci()
• f.round() -> f_round()
• load.libs() -> load_libs()
• lmer.fixef() -> lmer_fixef()
• omit.zeroes() -> omit_zeroes()
• base.breaks() -> base_breaks()
• base.breaks.x() -> base_breaks_x()
• base.breaks.y() -> base_breaks_y()
• plot.pointrange() -> plot_pointrange()

Install legacy apastats

If you need the pre-apastats2 code, install from the legacy branch/tag:

remotes::install_github("achetverikov/apastats@legacy-apastats")