02-2--main-preprocessing.Rmd

# Pre-processing {#main-preprocessing}

The methods and R codes to transforma data from the raw to tidy (analysis-friendly) form.

The final result of preprocessing must comply the Tidyverse style guide (https://style.tidyverse.org/) especially the variable names.
Pay attention that there are no guidelines for variable values.
Use package **styler** for automatic corrections.