Visualization Terms

Some more basic terms for visualisation introduction.

data semantics

the real world meaning, what does a data point actually represent?

data types

structural or mathematical interpretation of the data

why are semantics and types important?

they influence our choice of visual representation

categorical/ nominal attributes

discrete values in a single category with no intrinsic ordering

categorical/ nominal attribute examples

movie genre, city name, student name

ordinal attributes (ordered)

discrete values in a single category with an implicit, well-defined ordering

ordinal attributes (ordered) examples

movie rankings, customer satisfaction rankings

quantitative data (ordered)

measurements of magnitude upon which math operations make sense

quantitative data (ordered) examples

height, temperature, price

sequential ordering

range from minimum to maximum, e.g., age

diverging ordering

two sequences pointing in opposite directions and meeting at one point, e.g., temperature

cyclic ordering

values wrap back to starting point, e.g., time of day