r-trivia-night-melbourne2016

The following is a draft of questions used in R Trivia Night by R-Ladies Melbourne team

see also slides for a final draft

Potential questions for Trivia Night

1. Name two Australian women in Women in R Taskforce - Di Cook and Alicia Oshlack

2. What is the markup language of R Sweave documents? - latex

3. What does Literate Programming mean? - having code & text in one document

4. How to change the layout of console, source, view and environment panels in R Studio? - tools > Global options > pane layout

5. What is the expression that signals skipping the current iteration and going to the next iteration in a loop? - next

6. What argument preserves the structure of a matrix, if the result of subsetting is a vector? - m[ , 1, drop = FALSE]

7. The command to check if all rows in a matrix/data frame have non-NA values? - complete.cases()

8. What is the act of estimating a missing value from a neighbourhood group of values called? imputation

9. Shortcut to comment/uncomment a block of code - command/ctrl + shift + c

10. Shortcut for command execution in Windows - ctrl + enter

11. An Rstudio Service that facilitates interactive data analysis: a) Rstudio Server b) Shiny c) RMarkdown

12. The most popular CRAN package for data visualisation based on grammar of graphics - ggplot2

13. A R package for interactive data visualisation -plotly

14. R base package for faceted plots - lattice

15. What is the R package that provides an API for codes written in C/C++ programming languages? Rccp

16. What is the command set before generating random numbers that ensures reproducibility -set.seed()

17. This markup enables users to embed code in the textual analysis/reports - Rmarkdown

18. The function used to extract code from Rmarkdown documents - purl()

19. A R package that is used for writing books and other publications - pandoc

20. What is a makefile?

21. This package is used to predict gender based on the first names - genderizer

22. A package that is rapidly becoming popular for working with data frames - dplyr

23. What is %>% notation called in dplyr terminology? - pipe

24. Which code is more efficient ( m is a matrix)? for (i in 1:ncol(m)) { sum(m[ ,i]) } apply(m, 2, sum) colSums(m) - because of vectorisation

25. Who is the author of Advanced R & R Packages books? Hadley

26. Where the next UseR (UseR2017) conference is going to be held? Brussels, Belgium

27. When a library is loaded, it is added to the … search path

28. Sd in base R calculates the Standard Deviation. If a function with the similar name ‘sd’ is defined in the working directory, which of these two is evaluated when sd() is called? sd() in base R sd() defined in Working Directory

29. Name one R package for Parallel programming/parallelization - snow, parallel

30. Name a function that lists files in a directory based on a pattern or a suffix list.files()

31. What is the the function that writes console output to a file sink()

32. Default delimiter in read.table() - tab

33. This character invokes help page for a function -?

34. Write down all possible package names that you can guess using any letters from the pool ( a pool of letters from which the names of up to 4 packages could be recovered - to be made)

35. What is the function used to execute command-line/shell commands from within R? - system() or system2()

36. What does CRAN stands for? The Comprehensive R Archive Network

37. What is a (CRAN) Task View? Each Task View is a category of R packages developed for similar purposes

38. How to install packages from CRAN and GitHub? install.packages() install_github()

39. What is git? A version control system

40. How many CRAN mirrors are there for Australia? 2- CRAN minors are country-specific repositories to download R

41. What does the following commands do? grep(pattern, x) - returns index grep(pattern, x, value = TRUE) -returns the grepped value grep(pattern, x, invert = TRUE) - returns everything but the one with matches to the pattern specified gsub() - pattern replacement paste() vs paste0() - string concatenation

42. Name all the apply family-functions apply, vapply, lapply, sapply

43. What is the difference between grep() and grepl()? Answer needed

44. Who invented the S programming language the predecessor of R? John Chambers

45. What is global environment? Same as the current working directory

46. A function that reads the lines of a file with unknown delimiter. - readLines()

47. How do you out of a get out of a misspelled command in the R console? Press esc

Graphical round

Give a set of pictures from different ggplot geoms and they need to detect which geom has been used!