Contents

R Exercise

OASIS Data

You will be working with the oasis longitudinal dataset (OASIS 2). This is a free, open access dataset consisting of longitudinal MRI data in nondemented and demented older adults.

We’ll be downloading the data from http://www.oasis-brains.org/pdf/oasis_longitudinal.csv.

For those interested, a full explanation of the data can be found in:

Open Access Series of Imaging Studies (OASIS): Longitudinal MRI Data in Nondemented and Demented Older Adults. Marcus, DS, Fotenos, AF, Csernansky, JG, Morris, JC, Buckner, RL, 2010. Journal of Cognitive Neuroscience, 22, 2677-2684. doi: 10.1162/jocn.2009.21407

Reproduce and extend an analysis.

A small piece of exploratory analysis was done on the oasis dataset. While it was done in RMarkdown only the a html document is available. You want to reproduce and update this analysis.

  1. View the html report by right clicking on R Worksheet in the left hand menu, opening the link in a new tab.

  2. Create a fresh RMarkdown document and reproduce the given report. You’ll need to look at the cheat-sheet and you can copy and paste chunks of code if you wish.

  3. Knit to a pdf by selecting Knit to pdf from the Knit menu. How does the front matter change?

Advanced task

  1. View the advanced html report by right clicking on R Worksheet Advanced in the left hand menu, opening the link in a new tab.

  2. Adapt your RMarkdown document so that your report includes the additional features in the advanced report

Literate programming and RMarkdown R Worksheet