Chapter 2 Installation and Preparation

2.1 Installing via CRAN

You can install eyeTrackR via CRAN in the same way that you would install most R packages:

install.packages("eyeTrackR")

Alternatively, in RStudio, head over to the Packages tab, click Install and search for eyeTrackR.

2.2 Installing via Devtools

From R using the devtools package:

library(devtools)
install_github('hjgodwin/eyetrackR/source')

2.3 Required Files

To start with, you’ll need to output three different types of report from SR Research DataViewer. You’ll need:

• Fixation Report
• Message Report
• Interest Area Report

When I generate these reports, I typically get DataViewer to output every single column of data it can. It has a whole bunch of different ones, but my preference is to be greedy. The simple reason for this is that DataViewer can take a long, long time to load up and output all your data, so you don’t want to have to go back into it and do everything again just because you’ve missed a vital column. That being said, if you have a lower-spec or older computer, or are short on space, you may struggle with these files.

When saving these reports, it’s best to save them as tab-delimited text files (.txt).

2.4 Required R Skills

Before using eyeTrackR and the output it provides, you may well want to get familiar with the excellent data.table package. I use that extensively in this guide, so you may want to learn about that first, or in addition to, going through this.

There’s a very helpful introduction to using data.table available here.

2.5 Removing eyeTrackR

Please don’t!!

Ok, if you want to, either to update it or because you just want to get rid of it, run the following from R:

remove.packages(pkgs="eyeTrackR")