There are 2 important factors that influence how accurate your data will be with Ava:
1. How much sleep you get - you'll need to wear the Ava for at least four hours with three hours of sleep recorded, in order for there to be enough data to be incorporated into the algorithm to give you accurate predictions
2. How regular your sleep schedule is - your data will be more accurate if you go to bed and wake up around the same time each day.
It doesn't need to be perfect or exactly the same time every day but if, for example, you work the night shift a few nights per week and sleep on a more regular schedule for the rest of the week, this could influence your data.