{"id":20131620,"url":"https://github.com/avallecam/powder","last_synced_at":"2026-05-13T04:04:12.068Z","repository":{"id":138785904,"uuid":"240771164","full_name":"avallecam/powder","owner":"avallecam","description":"A Tidy Extension for Power Analysis","archived":false,"fork":false,"pushed_at":"2021-03-23T18:12:35.000Z","size":461,"stargazers_count":0,"open_issues_count":3,"forks_count":0,"subscribers_count":1,"default_branch":"master","last_synced_at":"2025-12-01T04:38:40.356Z","etag":null,"topics":["power-analysis","pwr-package","rstats","sample-size","tidyverse"],"latest_commit_sha":null,"homepage":"https://avallecam.github.io/powder/","language":"R","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"other","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/avallecam.png","metadata":{"files":{"readme":"README.Rmd","changelog":null,"contributing":".github/CONTRIBUTING.md","funding":null,"license":"LICENSE","code_of_conduct":".github/CODE_OF_CONDUCT.md","threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":".github/SUPPORT.md","governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null}},"created_at":"2020-02-15T18:55:23.000Z","updated_at":"2021-03-23T18:08:27.000Z","dependencies_parsed_at":null,"dependency_job_id":"f3387e84-3cee-4dfa-87f0-5396f0e63b5a","html_url":"https://github.com/avallecam/powder","commit_stats":null,"previous_names":[],"tags_count":2,"template":false,"template_full_name":null,"purl":"pkg:github/avallecam/powder","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/avallecam%2Fpowder","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/avallecam%2Fpowder/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/avallecam%2Fpowder/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/avallecam%2Fpowder/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/avallecam","download_url":"https://codeload.github.com/avallecam/powder/tar.gz/refs/heads/master","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/avallecam%2Fpowder/sbom","scorecard":null,"host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":286080680,"owners_count":32542201,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2026-05-02T12:25:33.646Z","status":"ssl_error","status_checked_at":"2026-05-02T12:24:51.733Z","response_time":132,"last_error":"SSL_read: unexpected eof while reading","robots_txt_status":"success","robots_txt_updated_at":"2025-07-24T06:49:26.215Z","robots_txt_url":"https://github.com/robots.txt","online":false,"can_crawl_api":true,"host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["power-analysis","pwr-package","rstats","sample-size","tidyverse"],"created_at":"2024-11-13T20:49:39.852Z","updated_at":"2026-05-13T04:04:12.038Z","avatar_url":"https://github.com/avallecam.png","language":"R","funding_links":[],"categories":[],"sub_categories":[],"readme":"---\noutput: \n  github_document:\n    #df_print: kable\n---\n\n\u003c!-- README.md is generated from README.Rmd. Please edit that file --\u003e\n\n```{r, include = FALSE}\nknitr::opts_chunk$set(\n  collapse = TRUE,\n  warning = FALSE,\n  comment = \"#\u003e\",\n  fig.path = \"man/figures/README-\",\n  out.width = \"100%\"\n)\n```\n\n# powder\n\n**Author:** [Andree Valle Campos](https://twitter.com/avallecam) \u003ca href=\"https://orcid.org/0000-0002-7779-481X\" target=\"orcid.widget\"\u003e\n\u003cimage class=\"orcid\" src=\"https://info.orcid.org/wp-content/uploads/2020/12/orcid_16x16.gif\" height=\"16\"\u003e\u003c/a\u003e\n\u003cbr/\u003e\n**License:** [MIT](https://opensource.org/licenses/MIT)\u003cbr/\u003e\n\n\u003c!-- badges: start --\u003e\n[![Lifecycle: experimental](https://img.shields.io/badge/lifecycle-experimental-orange.svg)](https://www.tidyverse.org/lifecycle/#experimental)\n[![CRAN status](https://www.r-pkg.org/badges/version/powder)](https://cran.r-project.org/package=powder)\n[![DOI](https://zenodo.org/badge/240771164.svg)](https://zenodo.org/badge/latestdoi/240771164)\n\u003c!-- badges: end --\u003e\n\n## Overview\n\nThe goal of `powder` is to extend __power__ and __sample size__ calculations:\n\n- for _more than one set_ of parameters, and\n\n- create tidy output _tables_ and _plots_ from them.  \n\n## Installation\n\nYou can install the developing version of `powder` using:\n\n```r\nif(!require(\"devtools\")) install.packages(\"devtools\")\ndevtools::install_github(\"avallecam/powder\")\n```\n\n\u003c!--\n\nYou can install the released version of powder from [CRAN](https://CRAN.R-project.org) with:\n\n``` r\ninstall.packages(\"powder\")\n```\n\n--\u003e\n\n## Quick example\n\nThis is a basic example which shows you how to solve a common problem:\n\n```{r example,eval=TRUE,message=FALSE}\nlibrary(tidyverse)\nlibrary(broom)\nlibrary(pwr)\nlibrary(powder)\n```\n\n```{r}\n#example(\"pwr.2p.test\")\npwr.2p.test(h=0.3,n=80,sig.level=0.05,alternative=\"greater\")\n\npwr_grid(h=0.3,n=seq(80,90,5),sig.level=0.05,alternative=\"greater\") %\u003e% \n  pwr_tidy(test_function = pwr.2p.test)\n\npwr_grid(h=seq(0.3,0.5,0.1),n=seq(80,90,5),sig.level=0.05,alternative=\"greater\") %\u003e% \n  pwr_tidy(test_function = pwr.2p.test)\n```\n\n## Core structure\n\n`powder` consist of three main functions:\n\n- `pwr_grid`: creates a tibble from all combination of input parameters using `tidyr::expand_grid`.\n\n- `pwr_tidy`: creates a `broom::tidy()` output from the calculations of all input parameters using `purrr::pmap`.\n\n- `pwr_plot`: create a `ggplot` with input parameters and calculated value (sample size, power or effect size)\n\n\n## More examples\n\n### One set of parameters\n\n```{r}\ndiff \u003c- 10\nsigma \u003c- 10\ndelta \u003c- diff/sigma\n\npwr.t.test(d = delta, power = 0.8, type = \"one.sample\")\n# sample - power plot\n#pwr.t.test(d = delta, power = 0.8, type = \"one.sample\") %\u003e% plot()\n```\n\n### More than one set of parameters\n\n#### sample size\n\n```{r}\n# stata\n# power onemean 20, diff(10 20 30) sd(10 12.5 15)\neg1 \u003c- pwr_grid(n = NULL,\n                diff = c(10,20,30),\n                sigma = c(10,12.5,15),\n                d = NULL,\n                sig.level = 0.05,\n                power = 0.8,\n                type = \"one.sample\",\n                alternative = \"two.sided\")\n\n#create tidytable\neg1 %\u003e% pwr_tidy(test_function = pwr.t.test)\n\n#create ggplot\neg1 %\u003e%\n  pwr_tidy(test_function = pwr.t.test) %\u003e%\n  pwr_plot(x = diff,y = n,group = sigma)\n```\n\n#### power\n\n```{r}\n# stata\n# power onemean 20, diff(5 (5) 15) sd(10) n(10 (2) 20)\neg2 \u003c- pwr_grid(n = seq(from = 10,to = 20,by = 2),\n                diff = seq(from = 5,to = 15,by = 5),\n                sigma = 10,\n                d = NULL,\n                sig.level = 0.05,\n                #power = 0.8,\n                type = \"one.sample\",\n                alternative = \"two.sided\")\n\n#create tidytable\neg2 %\u003e% pwr_tidy(test_function = pwr.t.test)\n\n#create ggplot\neg2 %\u003e%\n  pwr_tidy(test_function = pwr.t.test) %\u003e%\n  pwr_plot(x = n,y = power,group=diff)\n```\n\n## References\n\nStephane Champely (2018). pwr: Basic Functions for Power\n  Analysis. R package version 1.2-2.\n  https://CRAN.R-project.org/package=pwr\n\n## Citation\n\n```{r}\ncitation(\"powder\")\n```\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Favallecam%2Fpowder","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Favallecam%2Fpowder","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Favallecam%2Fpowder/lists"}