As far as I understand it, it kind of makes sense to me. I wonder if you would need a very large data set if the program was just for one person. I also wonder if you need an AI program for it at all, or if the difference between REM and non-REM is obvious. I have been toying with the idea of making something like this, with the hopes of making a cheap and easy REM detection device that you don't need to wear while asleep.