Time series visualization

The main characteristic of time series data is that the observations are taken at regular intervals. A plot of the time series values (the y axis) against the time itself (x axis) is of great importance and gives away many structural insights. A time series plot is not merely a scatterplot with time as the x axis. The time is non-decreasing and hence it has more importance and meaning in a time series plot than the mere x axis in a scatterplot. For instance, lines can connect the points of a time series plot that will indicate the path of the time series, and such a connection would be meaningless in the scatterplot, which would be all over the place. The path will generally indicate the trend and as such, shows in which direction the series will go next. Changes in time series are easily depicted in the plot. We will now visualize the different time series.

The plot.ts function is central to the scheme of visualization here. An external graphical device of appropriate...