stylo: R package for stylometric analyses

Authors: Maciej Eder^*, Mike Kestemont, Jan Rybicki
License: GPL-3

This package provides a number of functions, supplemented by a GUI, to perform various analyses in the field of computational stylistics, authorship attribution, etc.

Citation

If you find the package stylo useful and plan to publish your results, please consider citing the following paper:

Eder, M., Rybicki, J. and Kestemont, M. (2016). Stylometry with R: a package for computational text analysis. R Journal, 8(1): 107-21. https://journal.r-project.org/archive/2016/RJ-2016-007/index.html

Installation

There are three ways of installing stylo:

• from CRAN repository
• from the GitHub repository, via the package devtools
• from a locally downloaded file

1. Installing from CRAN

Launch R, make sure you are connected to the internet, type:

install.packages("stylo")

choose your favorite CRAN mirror (a window will pop up), click OK.

NOTE (Mac OS users): the package “stylo” requires X11 support being installed. To quote "R for Mac OS X FAQ" (http://cran.r-project.org/bin/macosx/RMacOSX-FAQ.html): “Each binary distribution of R available through CRAN is build to use the X11 implementation of Tcl/Tk. Of course a X windows server has to be started first: this should happen automatically on OS X, provided it has been installed (it needs a separate install on Mountain Lion or later). The first time things are done in the X server there can be a long delay whilst a font cache is constructed; starting the server can take several seconds.”

You might also run into encoding errors when you start up R (e.g. “WARNING: You're using a non-UTF8 locale” etc.). In that case, you should close R, open a new window in Applications > Terminal and execute the following line:

defaults write org.R-project.R force.LANG en_US.UTF-8

Next, close the Terminal and start up R again.

ANOTHER NOTE A slightly different workaround of the above problem (Mac users again):

• Install XQuartz, restart Mac
• Open Terminal, type: sudo ln -s /opt/X11 /usr/X11
• Run XQuartz
• Run R, type: system ('defaults write org.R-project.R force.LANG en_US.UTF-8')

2. Installing from the GitHub repository

A convenient way to install R packages directly from the GitHub repository is to use the package devtools. Unless you have already installed it, you should do it now:

install.packages("devtools")

Then, install the package stylo

library(devtools)
install_github("computationalstylistics/stylo")

3. Installing from a local file

Download the package from here; save the file anywhere on your computer where you will be able to find it; launch R; set working directory to the folder where the downloaded file is (please keep it mind that the slashes might look different in different operating systems):

setwd("i/hope/i/can/remember/where/it/was/")

Install the package:

install.packages("stylo_0.6.5.tar.gz", repos = NULL, type = "source")

NOTE: the stylo package requires a few standard R packages to be installed. When installing from CRAN or from GitHub, the dependencies are downloaded automatically; otherwise, you have to install them manually. Type (or copy-paste) the following lines:

install.packages("tcltk2")
install.packages("ape")
install.packages("class")
install.packages("e1071")
install.packages("pamr")
install.packages("tsne")

Usage

This section is meant to give the users a general outline of what the package can do, rather than providing a comprehensive description of designing a stylometric test using the R package stylo. Refer to the following documents:

• for (real) beginners: a crush introduction in the form of a slideshow
• for (sort of) beginners: a concise HOWTO
• for advanced users: a paper in R Journal
• full documentation at CRAN

Docs on non-obvious functions

• Authorship verification with the package 'stylo'
• Cross-validation using the function classify()
• Custom distance measures
• Testing rolling stylometry

Other relevant resources

• Despite a black legend, R and Python are not necessarily in a deadly clash: here is a great post by José Calvo Tello on invoking the package stylo directly from Python!

• Using the package stylo with the TXM environment: see this post by Serge Heiden.

• Probably not a bad idea to check a comprehensive Stylometry Bibliography curated by Christof Schöch, before starting an experiment in text analysis.

• The package stylo has been created as a by-product of a few projects conducted by the Computational Stylistics Group. See this website for further details. An older version of the webpage is also there, even if it has not been be updated for a while.