• R is a language and environment for statistical computing and graphics
• Open source
• The most widely used statistical software in the world
• Amazing number of contributors

Who use R?

• Researchers
• Data analysts
• Programmers
• Journalists
• Web designers

• In academia R de-facto is the standard tool

Illustration

https://www.r-users.com

http://blog.revolutionanalytics.com/2014/05/companies-using-r-in-2014.html

Why R?

“R offers a breadth and depth in statistical computing beyond what is available in commercial closed source products. Yet R remains, primarily, a programming language for the highly skilled statistician, and out of the reach of many.”

Williams, G. J. (2009). Rattle: A Data Mining GUI for R. The R Journal, 1/2, 45-55.

PRO

• Open source
• Reproducible
• Easy and fast to work with large datasets

• Most importantly, R can easily replace most of the tools one uses daily for research

CONTRA

• Steep learning curve
• Not perfect for handling survey data (metadata)

https://ourworldindata.org

https://jschoeley.shinyapps.io/hmdexp

http://bancdadesced.uab.es/population_change/

http://www.global-migration.info

Election 2016: Exit Polls

http://www.nytimes.com/interactive/2016/11/08/us/politics/election-exit-polls.html

A Day in the Life of Americans

http://flowingdata.com/2015/12/15/a-day-in-the-life-of-americans

Where People Run in Major Cities

http://flowingdata.com/2014/02/05/where-people-run/

Reproducibility

• Reproducibility of scientific results is the main challenge of the modern academia
• Collaboration, Open Science (2015). Estimating the reproducibility of psychological science. Science, 349(6251), aac4716. https://doi.org/10.1126/science.aac4716
• Out of 100 papers only 39 were replicated

Literate programming

• The idea of literate programming dates back to mid-80s
• The core idea: code, comments, and results should appear together in one document.

R notebooks

• The recently presented v1.0 version of RStudio brings R-notebooks as on of the main features.
  
• This type of document implements the principles of literate programming.

http://www.danielwells.me/human-lifespan-limit/

Swirl

• install.packages('swirl')
• library(swirl)
• swirl()

The most influential R developer

Hadley Wickham

tidyverse

https://blog.rstudio.org/2016/09/15/tidyverse-1-0-0/

tidy data

Wickham, H. (2014). Tidy Data. Journal of Statistical Software, 59(10). Retrieved from http://www.jstatsoft.org/v59/i10

Tidy data is a standard way of mapping the meaning of a dataset to its structure.

A dataset is messy or tidy depending on how rows, columns and tables are matched up with observations, variables and types.

In tidy data:

1. Each variable forms a column.
2. Each observation forms a row.
3. Each type of observational unit forms a table.

• Please follow me on the R script "examples-tidyverse.R"
• Then proceed to "exercises.R"

https://ikashnitsky.github.io/2017/data-acquisition-one//hmdexp

http://qz.com/316906/the-dude-map-how-american-men-refer-to-their-bros

Visualizing life tables

http://flowingdata.com/2016/01/19/how-you-will-die

https://www.r-bloggers.com/pisa-2015-how-to-readprocessplot-the-data-with-r

American schools

http://www.nytimes.com/interactive/2016/04/29/upshot/money-race-and-success-how-your-school-district-compares.html

• base
• lattice
• ggplot2

“The winner takes it all”

Strength of base plotting system

• Usually, base knows how to plot an object
• Extremely easy to use if you are happy with the default settings
• BUT
• Now ggplot2 has the autoplot function

The only example when ggplot2 failed for me

http://stackoverflow.com/questions/17753502

https://github.com/tidyverse/ggplot2/issues/1720

“gg” means “Grammar of graphics”

http://www.springer.com/us/book/9780387245447

Extremely big and helpful community

• Help
• Examples
• Rapid development
• Extensions

http://www.ggplot2-exts.org/gallery/

Amazing documentation

• Whenever you have a question on ggplot2, the first place to go is
• http://docs.ggplot2.org/current

http://docs.ggplot2.org/current

Please follow me on “examples-ggplot2.R”