The values in many data sets are recorded sequentially in time. Examples are
In such time series data, there is often a time-related pattern to the variability. This may be either a trend towards higher or lower values over time or a pattern that repeats regularly. This aspect of overall variability may be explained in terms of the time-ordering of the data.
Ignoring the time ordering and examining the data with dot plots or similar univariate techniques may result in useful information being missed.
Time series data are less common in biological applications than in business or other areas, so this chapter goes into less depth about analysis of time series than the other versions of CAST.
If you want to learn more about analysis of time series after studying this chapter, look at the General or Business CAST e-books.