Graphs for change is useful for Time Series Analysis .
They are used not only for the time but also for space.
By the way, almost all theories in Statistics and Machine Learning do not include the time-series changing.
But time-series changing is the common phenomena. So graphs for change is useful to fill the gap.
Time data is not neccesary for the time-siries graph if the order of the data is related to the time.
NEXT Line Graph