1.1 Calendar-based graphics

Visualisation is critical for understanding the data patterns, and for discovering the unexpected in data. Chapter 2 describes how to make a calendar layout for plots, so that human activity data can be examined in a familiar form. I develop a new method for assembling small multiples into a calendar layout. It is fully integrated into the grammar of graphics (Wilkinson 2005; Wickham 2009), specifying the plots as a functional mapping from data variables to graphical primitives. This new calendar-based display sketches the patterns of daily and sub-daily human behaviours, unlocking vivid and detailed data stories about the way we live. The chapter contains a comprehensive literature review related to calendar-based graphics.