A Note on Measures of Single Timeseries Activity in Resting-State fMRI Studies

Abstract

In statistics, signal processing and mathematical finance, a time series is a sequence of data points, measured typically at successive times spaced at uniform time intervals. Here, I only focus on the discrete time series. The motivation of writing this methodology note is to clarify the relationship between the measures to quantify activity of an observed timeseries. Particularly, focus one several measures used in recently emerged field of resting-state fMRI studies. Although all these measures have been extensively developed in EEG or other timeseries studies, many researchers focusing on various applications in or new comers to this new field need to know existed measures and the relationships among these measures.