Statistical Programming in R

Overview of this course

Program

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Goal of this course

Learn to keep your cool

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and build the foundation for a succesfull scripting career

What is R?

Software

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The origin of R

  • R is a language and environment for statistical computing and for graphics

  • GNU project (100% free software)

  • Managed by the R Foundation for Statistical Computing, Vienna, Austria.

  • Community-driven

  • Based on the object-oriented language S (1975)

What is RStudio?

Integrated Development Environment (IDE)

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RStudio

  • Aggregates all convenient information and procedures into one single place
  • Allows you to work in projects
  • Manages your code with highlighting
  • Gives extra functionality (Shiny, knitr, markdown, LaTeX)
  • Allows for integration with version control routines, such as Git.

How does R work

Objects and elements

  • R works with objects that consist of elements. The smallest elements are numbers and characters.

    • These elements are assigned to objects.
    • A set of objects can be used to perform calculations
    • Calculations can be presented as functions
    • Functions are used to perform calculations and return new objects, containing calculated (or estimated) elements.

The help

  • Everything that is published on the Comprehensive R Archive Network (CRAN) and is aimed at R users, must be accompanied by a help file.
  • If you know the name of the function that performs an operation, e.g. anova(), then you just type ?anova or help(anova) in the console.
  • If you do not know the name of the function: type ?? followed by your search criterion. For example ??anova returns a list of all help pages that contain the word ‘anova’

  • Alternatively, the internet will tell you almost everything you’d like to know and sites such as http://www.stackoverflow.com and http://www.stackexchange.com, as well as Google can be of tremendous help.
    • If you google R related issues; use ‘R:’ as a prefix in your search term

Assigning elements to objects

  • Assigning things in R is very straightforward:

    • you just use <-
  • For example, if you assign the value 100 (an element) to object a, you would type

a <- 100

Calling objects

  • Calling things in R is also very straightforward:

    • you just use type the name you have given to the object
  • For example, we assigned the value 100 to object a. To call object a, we would type

a
## [1] 100

Writing code

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This is why we use R-Studio.

Practical A