Summary

Describes the construction of the Araucaria database and lists its sources, along with an account of the problems (bias) of small corpora.

They also present some ideas of what an argument corpus could be used for, both for teaching and for research.

Research uses of argument corpora

comparative research over time -- what kinds of arguments are used
comparative research over discourse fields
comparative research into different strategies for interpreting arguments (e.g. what semantic properties correspond to a given rhetorical type of argument)
testing how comprehensive/exhaustive the classification schemes or descriptive argument typologies are
evaluating the rationality of argumentative practices (they call this "critical application of normative models of argumentation")

facilitating decision-making within communities by sharing examples of "good practice" -- paradigmatic cases of good, realistic arguments
facilitating students' critical thinking through examples of "good practice"
facilitating students' critical thinking through examples of fallacious reasoning
facilitating students' critical thinking through practicing analytical skills by analyzing arguments
automating grading students' work in critical thinking -- e.g. regarding how arguments should be analyzed

The corpora has been used for other research, such as to detect argumentative vs. non-argumentative sentences (Automatic detection of arguments in legal texts).

They mention another existing corpora, the University of Durham's Free Britain Corpus, created to study arguments.