Notions of complexity surface in a number of different contexts: In theoretical linguistics, syntactic structures are analyzed in terms of their complexity and constraints such as the complex-NP constraint are formulated on this basis. In cognitive psychology, the complexity involved in cognitively processing language input in human sentence processing is studied. In second language acquisition research, the analysis of complexity is correlated with stages of acquisition (together with accuracy and fluency). On the applied side, complexity measures have long been used to determine the readability of a given text, and some readability measures have recently been automated in computational linguistics. Relatedly, some proposals for automatic text simplification have been published in recent years, to make information accessible to readers with low reading proficiency.

In this seminar, we will discuss the empirical and conceptual nature of these notions of complexity and explore where the formalization and automatic analysis offered by computational linguistics can lead to applications such as automatic readability measures, search engines supporting the filtering of results by complexity, and automatic text simplification.

Note that the following session plan is subject to change; it only constitutes the current state of our planning as the semester unfolds.

Nature of course and our expectations: This is a Hauptseminar which on the one hand intends to provide an overview of current perspectives and approaches on complexity in linguistics, psycholinguistics, and computational linguistics. On the other hand, the computational linguistics students enrolled in the course are expected to define and implement an approach for complexity analysis or text simplification as their term paper project.

Academic conduct and misconduct: Research is driven by discussion and free exchange of ideas, motivations, and perspectives. So you are encouraged to work in groups, discuss, and exchange ideas. At the same time, the foundation of the free exchange of ideas is that everyone is open about where they obtained which information. Concretely, this means you are expected to always make explicit when you’ve worked on something as a team – and keep in mind that being part of a team always means sharing the work.

For text you write, you always have to provide explicit references for any ideas or passages you reuse from somewhere else. Note that this includes text “found” on the web, where you should cite the url of the web site in case no more official publication is available.

Class etiquette: Please do not read or work on materials for other classes in our seminar. Come to class on time and do not pack up early. When our seminar meets in the computer lab, only use the computers when you are asked to do a specific activity – do not read email or browse the web. All portable electronic devices such as cell phones should be switched off for the entire length of the flight, oops, class. If for some reason, you must leave early or you have an important call coming in, or you have to miss class for an important reason, please let the instructor know before class.

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