R Programming Language Certification Data Visualization & Reporting

Question 1

Which R package is most widely used for creating layered, publication-quality graphics?

Accepted Answer

ggplot2

Answer

lattice

Answer

base graphics

Answer

plotly

Question 2

In ggplot2, which function adds a scatter plot layer to a plot?

Accepted Answer

geom_point()

Answer

geom_line()

Answer

geom_bar()

Answer

geom_histogram()

Question 3

What does the aes() function define in ggplot2?

Accepted Answer

Aesthetic mappings between data variables and visual properties

Answer

Plot colors and fonts

Answer

Axis labels and titles

Answer

Theme settings

Question 4

Which ggplot2 function creates separate panels for subsets of data?

Accepted Answer

facet_wrap()

Answer

split_plot()

Answer

panel_grid()

Answer

group_plot()

Question 5

In R Markdown, which chunk option prevents code from being displayed in the output?

Accepted Answer

echo=FALSE

Answer

echo=TRUE

Answer

eval=FALSE

Answer

include=FALSE

Question 6

Which function saves a ggplot2 plot to a file?

Accepted Answer

ggsave()

Answer

save_plot()

Answer

export_plot()

Answer

write_plot()