Always look on the bright side of plots

Everyone who creates visualizations in R is bound to make mistakes that prevent their plots from looking as they should. Sometimes, these mistakes create beautiful "accidental aRt", though other times they're just plain frustrating. Either way, however, there's something to be learned. This talk will draw on years of watching both the ggplot2 issue tracker and the @accidental__aRt twitter account to highlight some common plot foibles and explain what they can teach us about how ggplot2 works.

Transcript

1. @kara_woo
   
   
   rstudio::global(2021)
   always look on the bright
   side of plots
   

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2. (clockwise from top le
   ft
   ): miles mcbain, alex hanna, noam ross, julia silge, jacqueline nolis, jarvis miller
   
   
   @accidental__aRt
   

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3. sarah kilian
   

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4. the prac
   ti
   cal dev, cc-by-nc 2.0
   

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7. created with danielle navarro’s
   fl
   ametree package
   

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8. mapping mishaps
   

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9. aesthetics map visual properties to
   variables in your data
   

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10. data from the palmerpenguins package by
    
    
    allison horst, alison hill, & kristen gorman
    

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11. penguin_plot +
    
    
    geom_text(
    
    
    aes(x = 195, y = 55, label = "Chinstrap")
    
    
    )
    
    
    

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14. library("ggrepel")
    
    
    penguin_plot +
    
    
    geom_text_repel(
    
    
    aes(x = 195, y = 55, label = "Chinstrap")
    
    
    )
    
    
    

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16. we’ve written “Chinstrap”
    

    `r nrow(penguins)`
    
    
    times
    

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17. we’ve written “Chinstrap”
    
    
    344
    
    
    times
    

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18. penguin_plot +
    
    
    geom_text(
    
    
    aes(x = 195, y = 55, label = "Chinstrap")
    
    
    )
    
    
    

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19. penguin_plot +
    
    
    annotate(
    
    
    geom = "text",
    
    
    x = 195,
    
    
    y = 55,
    
    
    label = "Chinstrap"
    
    
    )
    

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23. scale snafus
    

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24. scales convert values from the data
    space to the aesthetic space
    

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25. coordinate systems draw axes and
    panels
    

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27. penguin_plot +
    
    
    scale_x_continuous(limits = c(200, NA))
    
    
    penguin_plot +
    
    
    coord_cartesian(xlim = c(200, NA))
    

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30. scale transformation occurs before
    statistical summaries
    

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31. setting coordinate limits zooms in
    the plot
    

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33. penguin_plot +
    
    
    scale_x_continuous(limits = c(200, NA))
    
    
    penguin_plot +
    
    
    coord_cartesian(xlim = c(200, NA))
    

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34. penguin_plot +
    
    
    scale_x_continuous(limits = c(200, NA))
    
    
    #> Warning: Removed 192 rows containing non-
    finite values (stat_smooth).
    
    
    #> Warning: Removed 192 rows containing missing
    values (geom_point).
    
    
    penguin_plot +
    
    
    coord_cartesian(xlim = c(200, NA))
    ⚠
    

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35. theme threats
    

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36. themes customize the look and feel
    of your plots
    

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37. text
    
    
    

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39. text
    
    
    └── axis.text
    
    
    

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41. text
    
    
    └── axis.text
    
    
    └── axis.text.x
    
    
    │
    
    
    │
    
    
    └── axis.text.y
    
    
    

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42. text
    
    
    └── axis.text
    
    
    └── axis.text.x
    
    
    │ └── axis.text.x.bottom
    
    
    │ └── axis.text.x.top
    
    
    └── axis.text.y
    
    
    └── axis.text.y.left
    
    
    └── axis.text.y.right
    

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44. penguin_plot +
    
    
    theme(
    
    
    axis.text.y = element_text(
    
    
    angle = 90,
    
    
    hjust = 1
    
    
    )
    
    
    )
    

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46. 🤔
    

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47. theme_grey
    
    
    #> function (…)
    
    
    #> {
    
    
    #> …
    
    
    #> axis.text.y = element_text(margin =
    margin(r = 0.8 * half_line/2), hjust = 1),
    
    
    #> axis.text.y.right = element_text(margin =
    margin(l = 0.8 * half_line/2), hjust = 0),
    
    
    #> …
    
    
    #> }
    

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48. the most specific theme element
    wins
    

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49. penguin_plot +
    
    
    theme(
    
    
    axis.text.y.left = element_text(
    
    
    angle = 90,
    
    
    hjust = 1
    
    
    ),
    
    
    axis.text.y.right = element_text(
    
    
    angle = 90,
    
    
    hjust = 1
    
    
    )
    
    
    )
    

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52. mapping mishaps
    

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53. mapping mishaps
    scale snafus
    

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54. mapping mishaps
    scale snafus
    theme threats
    

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55. chapter 13: mastering the grammar
    ggplot2-book.org
    

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56. ggplot(states, aes(x = long, y = lat)) +
    
    
    geom_polygon() +
    
    
    coord_map()
    

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57. rstd.io/global2021/karawoo
    

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