Frequently Asked Questions

Data Management

  • How to Input data into R
  • How can I read binary data into R?
  • How can I write a binary data file by column?
  • How can I write a binary data file by row?
  • How can I sort my data in R?
  • How can I format a string containing a date into R “Date” object?
  • How can I get a table of basic descriptive statistics for my variables?
  • How can I subset a data set?
  • How can I identify the first and last observations within a group in R?
  • How does R handle missing values?
  • How does R handle date values?
  • How can I reshape my data in R?
  • How can I “collapse” my data in R?
  • How can I convert from person-level to person-period?

R Interface

  • How can I see what data sets are available when I started R?

The very basics of R

  • How can I save my data and graphs in a different format?
  • How can I manage R packages?
  • How can I time my code?


  • How can I overlay plots in a trellis graph?
  • How can I make spaghetti plots?
  • How can I visualize longitudinal data in ggplot2?
  • How can I do a scatterplot with regression line or any other lines?
  • How can I change the angle of the value labels on my axes?
  • How can I add features or dimensions to my bar plot?


  • How can I calculate Moran’s I in R?
  • How can I perform Mantel’s test in R?
  • How can I generate a variogram for spatial data in R?
  • How can I generate a Venn diagram in R?
  • How do I fit a variogram model to my spatial data in R using regression commands?
  • How do I model a spatially autocorrelated outcome?
  • How can I manage and plot social network data?
  • How can I generate bootstrap statistics in R?
  • How can I estimate the standard error of a transformed parameter in R using the delta method?
  • How can I do post-hoc pairwise comparisons in R?
  • How can I get Type III tests of fixed effects in R?
  • How can I explain a continuous by continuous interaction?
  • How can I perform seemingly unrelated regression in R?
  • How can I test contrasts in R?


  • How does R handle overlapping object names?