Smooth Operator: Step Towards a Generalized Smoothing Framework
Advisor: Dr. Kexin Rong, Course: Human-in-the-loop Data Analytics
Report : Smooth Operator: Step Towards a Generalized Smoothing Framework
Today’s visualization systems typically plot noisy raw data that obscures long-term trends from the user. In this project, we suggested steps toward developing a general framework to automate time-series smoothing. We explored different smoothing functions and statistical measures for smoothing a time series. We analyzed the results of our user study qualitatively and quantitatively to explore correlations between different time series and optimum smoothing techniques.
The figure above represents the variation in smoothing of the weekly homicides in Chicago dataset by changing the smoothing function and statistical measure.
We use a combination of statistical measure and smoothing function to smooth a time series. Further, we use the standard deviation of the first differences of the smoothed time series as a measure of roughness of the time series. For a given combination of statistical measure and smoothing function, our algorithm computes the optimal smoothing length.
We conducted a user study to gauge people’s preferences of the best combinations of smoothing function and statistical measure for different datasets.
Our recommendations for dealing with seasonal and noisy time series are based on extensive evaluations stated in our Paper, and we believe that they can be helpful in improv- ing the reliability and accuracy of smoothing time series.