DataVis.ca
Michael Friendly
York University
ACCENT Principles for effective graphical display
The essence of a graph is the clear communication of quantitative information. The ACCENT principles emphasize, or accent, six aspects that determine the effectiveness of a visual display for portraying data.- Apprehension:
- Ability to corectly perceive relations among variables.
Does the graph maximize apprehension of the relations among variables? - Clarity:
- Ability to visually distinguish all the elements of a graph.
Are the most important elements or relations visually most prominent? - Consistency:
- Ability to interpret a graph based on similarity to previous graphs.
Are the elements, symbol shapes and colors consistent with their use in previous graphs? - Efficiency:
- Ability to portray a possibly complex relation in as simple a way as possible.
Are the elements of the graph economically used?
Is the graph easy to interpret? - Necessity:
- The need for the graph, and the graphical elements.
Is the graph a more useful way to represent the data than alternatives (table, text)?
Are all the graph elements necessary to convey the relations? - Truthfulness:
- Ability to determine the true value represented by any graphical element by its magnitude relative to the implicit or explicit scale.
Are the graph elements accurately positioned and scaled?
Adapted from: D. A. Burn (1993), "Designing Effective Statistical Graphs". In C. R. Rao, ed., Handbook of Statistics, vol. 9, Chapter 22.
