I have conducted an experiment where several students assigned to two different groups had to solve 13 different puzzles each in two different sessions. Thus, we have 2 sessions, and two different tasks with 13 puzzles each are needed to be solved.
For example: if subjects solve 1 puzzle within a task, they completed 1/13 or 7.6% of the task, if they solved all puzzles, they have completed 100% of the task.
Then my dependent variable goes from 0 to 100% (100% of productivity if all puzzles are solved) in each of the sessions.
The data might look like this: SUBJECT SESSION TASK PRODUCTIVITY 1 1 2 20% 1 2 1 10% 2 1 1 50% ...
I heard that a Linear Mixed Model (LMM) considers that the dependent variable is not restricted between 0 and 100. Do you know how may I analyze those cases with a LMM?
May I use nlme or lmer?