Around 20% of GRE questions involve "data analysis" -- essentially reading graphs and tables to determine what they mean, and then applying that knowledge. These questions are generally fairly straightforward, and the key is to be able to read the graphs/tables and to understand concepts like the mean, median, mode, interquartile range, standard deviation, and so on.
We have broken up this guide into five main sections and an appendix:
(Note that posts are still in the process of being written; caveat emptor!)
- What is Data? Variables and frequencies
- Statistical Concepts
- Reading Graphs: An Introduction
- Normal distribution
- Why does it matter?
- Standard normal distribution
- Finding the standard deviation
- Appendix: Understanding All the Graphs