Dear Forum,
I'm planning an event for 250 people coming from different countries. During this event we have 32 different workshops over 2 days: 23 of them are given twice; 9 of them are double-length and are given once.
Some facts are as follows:
--Each of these workshops has a different theme and sub-theme (example: "communication" as a theme, "digital communication" as a sub-theme)
--8 workshops occur concurrently, 4 per day (one session right after the other)
--The double-length workshops have double the attendees of the single workshops
Some constraints and optimization:
--Each workshop is led by an attendee; I would like to minimize the number of other attendees to that workshop from that same country
--I would like to maximize variety for participants to the sub-themes
--I would like to maximize variety for participants to the other countries' workshops
--Some workshops are stronger than others in terms of quality; I would like to provide a good mix of strong and less-strong workshops to each attendee
--To minimize chaos in switching rooms, I would like to keep groups together for at least 2 consecutive sessions (i.e. if we have sessions A-B-C-D on Day 1 and E-F-G-H on Day 2, we could have switching between B and C, and then between F and G)
Overall I thought of dividing the 250 attendees into 10 groups of 25. At any one time, I have two double length sessions going on (covering A-B and then C-D) so 2 groups each are in those rooms. There will be one period where we have 3 double-length sessions going on, but I can handle this as an exception.
However, to maximize variety, I could mix around the groups on Day 2 instead of keeping them all together throughout the 2 days.
Basic questions:
--How should I enter the "subjects"? Would I go by theme, sub-theme, or workshop title?
--How should I allocate the groups and students? I want each group to have a mix of nationalities, but it's not necessary that they stay together for the entire time. In fact, I suspect I could do up to 40 groups: 10 which attend sessions A-B, then a new 10 to attend C-D, a new 10 for E-F, a new 10 for G-H. The constraint would be that a particular participant not attend the same session twice.
Appreciate the help - I've been going through various tutorials but cannot find anything analogous to my situation!
Hello and Welcome!
There was a situation like yours, here, recently: http://lalescu.ro/liviu/fet/forum/index.php?topic=1039.0 (see near the end of the thread, where we came up with (probably) a correct solution).
If you want randomization, I would advise you to add (like in the mentioned thread) an activity for each hour and for each student, without teacher and with an unspecified room. FET will allocate students randomly. In the new FET-5.15.0 you have 2 useful constraints, which may help in this case: activities occupy max time slots from selection and constraint activities max simultaneous in selected time slots.
About subject name choice, it's up to you. Remember that you can add activity tags, unlimited number for each activity.
About room change, you have constraint students/teachers max building changes per day, but I am not sure you can use that, because many activities will have unspecified room.
Please let me know if the above works, then we'll talk about the rest of the problems, we may solve them with existing constraints and other tricks.
Dear Liviu,
Indeed I was trying to follow the logic in that post.
I'm unable to generate a timetable, I believe because I've set up my Students incorrectly.
May I send you my file?
Yes, sure :-)
Liviu - thanks for taking a look at my file.
What I realized is that FET won't allocate your students for you, so I will do that by hand. I can only suspect that such a problem increases the complexity exponentially. However, if you are thinking of going down this road in future developments, I would vote in favor of having such a feature where students can have "tag preferences". The user would set "minimum or maximum number of tags a student group must have". This would then be an optimization problem to try to get the most students with their preferences. Essentially FET would form student groups as an output rather than as an input.
At the end of it all, FET seems to have helped me out by minimizing the number of room changes, something that would be chaotic for my event. Furthermore, the report of having a "student" view will be very handy.
Thanks again for your speedy support, Liviu!
I'll add your suggestion in the TODO file. Please let me know the exact words, or should I add your previous post as it is?