Generalising from data
Most data sets do not arise from randomly sampling individuals from a finite population. However we are still rarely interested in the specific individuals from whom data were collected — we want to generalise from the data.
The recorded data are often 'representative' of something more general.
Examples
We can (and should!) use exploratory graphical and numerical summaries to help understand the distribution of values in data sets such as these. But what do the data tell us about the underlying process?