A method for reducing a data size of user data associated with a sleep session, the method comprising: receiving , from one or more sensors , first user data associated with a first sleep session of a user ; determining that the first user data comprises at least a first instance of a first sleep feature and a second instance of the first sleep feature, the first sleep feature being a first data size; determining a first value representing the first instance during a first temporal interval; determining a second value representing the second instance occurring during a second temporal interval; determining first encoding data representing the first value, the first encoding data being a second data size that is less than the first data size; determining second encoding data representing the second value, the second encoding data being a third data size that is less than the first data size; generating second user data by encoding the first user data using the first encoding data to represent the first instance in the second user data and encoding the first user data using the second encoding data to represent the second instance in the second user data; storing the second user data; obtaining the first encoding data and the second encoding data; obtaining the second user data; identifying that the first encoding data is associated with the first value occurring during the first temporal interval and that the second encoding data is associated with the second value occurring during the second temporal interval; and generating third user data representing the first value and the second value, wherein the third user data comprises a first reference version of the first value and a second reference version of the second value arranged based on a temporal ordering of the first temporal interval and the second temporal interval. receiving , from one or more sensors , first user data associated with a first sleep session of a user ; determining that the first user data comprises at least a first instance of a first sleep feature and a second instance of the first sleep feature, the first sleep feature being a first data size; determining a first value representing the first instance during a first temporal interval; determining a second value representing the second instance occurring during a second temporal interval; determining first encoding data representing the first value, the first encoding data being a second data size that is less than the first data size; determining second encoding data representing the second value, the second encoding data being a third data size that is less than the first data size; generating second user data by encoding the first user data using the first encoding data to represent the first instance in the second user data and encoding the first user data using the second encoding data to represent the second instance in the second user data; storing the second user data; obtaining the first encoding data and the second encoding data; obtaining the second user data; identifying that the first encoding data is associated with the first value occurring during the first temporal interval and that the second encoding data is associated with the second value occurring during the second temporal interval; and generating third user data representing the first value and the second value, wherein the third user data comprises a first reference version of the first value and a second reference version of the second value arranged based on a temporal ordering of the first temporal interval and the second temporal interval. <EOS>