David Shellard

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  • A bar chart plots the number of times a particular value or category occurs in a data set, with the length of the bar representing the number of observations with that score or in that category.
  • Commonly used on maps, and x/y-axis plots, or no plot at all, bubble charts communicate the raw count, frequency, or proportion of some variable where the size of the bubble reflects the quantity.
  • GIS mapping will typically display one data variable or indicator, often using colour coding to indicate the density, frequency, or percentage in a given region, allowing quick comparison between regions.
  • A matrix chart shows relationships between two or more variables in a data set in grid format.
  • A histogram is a graphical way of presenting a frequency distribution of quantitative data organised into a number equally spaced intervals or bins (e.g. 1-10, 11-20…).
  • Stacked graphs depict items stacked one on top (column) of the other or side-by-side (bar), differentiated by coloured bars or strips.