Handbook for PhD Students
This PhD Handbook serves a dual purpose: it describes the research methodology of our group and gives general advice to students, and it sets out the standards and processes that all students in the group are expected to strive for.
My advice for finding open problems and challenge tasks:
Read: Start by reading papers in your area. In the process, try to identify limitations in existing algorithms, such as restrictive assumptions in the used models and algorithms. Assumptions in evaluation settings may also hint at limitations of the algorithms. Try to identify common limitations across algorithms to maximise the relevance and impact of your work. Survey papers often contain sections on open problems which can give useful inspiration (e.g. [1], [2], [3]). Once a technical problem has been identified, try to formulate challenge tasks which require a solution to the problem.
Play: Implement a collection of state-of-the-art and/or baseline algorithms in the field and test them on some recent benchmark tasks. By using these algorithms to solve difficult tasks, you will gain a deeper understanding of their inner workings and their limitations, some of which may not be apparent from their original papers. Based on this experience, try to identify important open problems and new challenge tasks, for example by modifying the tested benchmark tasks to highlight the open problem.
Talk: Seek out and use opportunities to talk about your research and the research of others, whether in informal chats or formal presentations (e.g. group meetings, institute seminars, conferences/workshops, etc). Talking about your work requires you to express your ideas in a clear and succinct way, and is an important channel to get feedback and suggestions from others. It often happens that PhD students bury themselves in their work, which carries a risk of missing out on useful ideas; talking with other people is one way to avoid that.