In the past, courses at the department were assigned to students via first-come first-served (FCFS). Many students and course organizers complained about the FCFS system. Students registered for several courses to make sure they get one of their preferred courses, but afterwards only accepted one of these courses. This made it almost impossible for course organizers to plan properly and many courses with a lot of registered students ended up with a low number of participants.
Stable matching mechanisms are nowadays widely used for course assignment, school choice, and other applications in order to avoid the problems mentioned above. There are two key features:
Firstly, students have a dominant strategy to reveal their preferences truthfully. They cannot make themselves better off by false reports.
Secondly, the outcome is stable such that there cannot be pairs of courses and students, that would like to switch after the matching is performed.
There is also no reason to be the first to submit the registration at a particular time. This way, the course organizers and the department gets much more information about the demand for different courses and they can better adapt to the needs of students in future periods.
We use the many-to-one version of the well-known algorithm by Gale and Shapley (1962), which is being used in large-scale applications such as the US National Resident Matching Program.
The theory around stable matching was honoured with the Nobel memorial prize in Economic Sciences in 2012.
Participation for course organizers is mandatory but voluntary for students. However, the primary seats by the course organizers are assigned via the stable matching tool. In exceptional cases, students can always approach course organizers after the matching directly and course organizers have a possibility to admit a student.
Course organizers do have a right to reject students after the matching if a student does not satisfy the prerequisites announced in TUMonline. Otherwise, students are accepted as long as the capacity announced by the course organizer in the matching system is not exceeded. Course organizers can specify all types of prerequisites that they also had in the past. Students are supposed to attend initial meetings to learn about all prerequisites and the course content. Attendance of this initial meeting can be made a prerequisite as well.
Course organizers assign seminar topics to students after the initial meeting and the matching.
Students who want to register for a second seminar, proseminar or lab course can only do so after the primary matching had been conducted. The department first wants to make sure that every student can attend at least one of these courses in each semester and this is given priority. However, typically there are additional course seats available after the matching which will be announced on the matching web site.
- The system stores preferences of students for one semester. This information is only accessible for the administrator. Afterwards the data will be deleted. There is a backup solution available during this time. Course organizers only see which students have expressed a preference for their course, but not which preference (1st, 2nd, etc.). This is done to respect the privacy of the students. Of course, there is a privacy statement, and the TUMonline Campus Management Team and privacy delegates were involved.