Power and Sample Size Calculations with R

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  Power and Sample Size Workshop
  

  
  

  Workshop Overview

  In this workshop, we will provide a brief review of the concepts underlying power and sample size analysis. Following this, we will use R for hands-on programming practice with power and sample size calculations for several different types of analyses, including parametric and nonparametric tests using both analytical and simulation approaches.

  Learning Objectives

  By the end of the workshop, participants should:

  1. Become familiar with concepts such as type I and II error, effect sizes, and confidence intervals
  2. Know how to do power and sample size calculations for several common study designs and tests
  3. Know how to create power and sample size plots from grid searches
  4. Know how to use simulations for more complex analyses
     

  Prerequisites

  A basic understanding of statistics and the purpose of doing power and sample size calculations, and familiarity with R programming will be helpful but not required.

  Software

  This course uses R and RStudio. Please have these installed on your laptop prior to the workshop.
  

     Install R
     Install RStudio

  Instructors

  
  

  Alan Paciorek is a Biostatistician with the UCSF Helen Diller Family Comprehensive Cancer Center, and a Programmer Analyst in the UCSF Deptartment of Epidemiology & Biostatistics.
  

  Karla Lindquist, PhD is the Scientific Lead for the Data Science Initiative in the UCSF Library.
  

  
  

  Materials
  

  All materials here are subject to periodic updates by the Instructor. Content on this website reflects the material taught during the most recently offered live workshop.
  

  This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License

  Upcoming Sessions
  

  Please check the library calendar to see when this course will be offered next. You can also sign up for the Library Data Science Newsletter to get notified when new courses are added to the schedule.

  Also check out the workshops offered under Programming and Bioinformatics, and by the Gladstone Institute.

  
  

  
  

  
  
• Select section Lecture slides

  Lecture slides

  • Select activity Power/sample size concepts

    

    Power/sample size concepts File
• Select section R code

  R code

  • Select activity Package installation/loading notebook

    

    Package installation/loading notebook File
  • Select activity Common study designs and test notebook

    

    Common study designs and test notebook File
  • Select activity Grid search and plot notebook

    

    Grid search and plot notebook File
  • Select activity Simulation notebook

    

    Simulation notebook File
• Select section Resources

  Resources

  Examples of other packages that can do more complex power/sample size calculations: 
  

  • For microarray experiments: https://bioconductor.org/packages/release/bioc/vignettes/sizepower/inst/doc/sizepower.pdf
    
  • For complex survey designs: https://cran.r-project.org/web/packages/samplesize4surveys/vignettes/Power-and-sample-size.html

  
  

  Alan Paciorek's effect size calculator for 2-way contingency tables (Excel spreadsheet)