My dataset contains a Likert item containing how energetic the participants were at that moment rated from 0-6. Where 0 = not energetic at all and 6 = very energetic. I have to investigate if these scores actually differ from one another based on the data. If 0 and 1 do not differ from eachother, I have to combine these two levels into one and so on. So at the end I might have 2 or 4 levels instead of 6.
I have tried applying classification algorithms to the data to see if a model classifying '0' would give an error rate when classifying '1'. Unfortunately, this did not work as I wanted. Is this actually possible?
My question is if someone knows how I can best investigate if there is indeed a difference between those 6 levels or whether I can combine some of them based on differences (or not) in the data of those levels.