Presentation on theme: "Theory of Data Graphics Part 1 Most of a graphic’s ink should vary in response to data variation (see chapters 4-6)"— Presentation transcript:
Theory of Data Graphics Part 1 Most of a graphic’s ink should vary in response to data variation (see chapters 4-6)
Chapter 4 - Data-Ink Ratio Data Ink is the ink on a graph that represents data. Tufte claims that good graphical representations maximize data-ink and erase as much non-data-ink as possible. Data-Ink Principles: 1. Above all else show data. 2. Maximize the data-ink ratio. 3. Erase non-data-ink. 4. Erase redundant data-ink. 5. Revise and edit
Data-Ink ratio of 1 Tufte tests these principles on a whole range of examples to come up with a wide range of fresh designs that dramatically improve the legibility of the graphs. Here is an example with a very high data-ink ratio. It’s an electroencephalogram – a graph that records the electrical activity from the brain. This graph would have a data-ink ratio of 1.
CH. 5 - Chartjunk Moiré vibration Grids 1 vs 212 Ducks (self-promoting graphs that are used to demonstrate the graphic ability of the designer rather than display the data.)
Worst chart ever? “A series of weird three-dimensional displays appearing in the magazine of American Education in the 1970’s delighted the connoisseurs of the graphically preposterous. Here five colors report, almost by happenstance, only 5 pieces of data (since the division within each adds to 100%). This may well be the worst graphic ever to find its way into print.” See page 118.
Chapter 6 – Data-Ink Maximization See chart redesign pages
Multifunctioning Graphical Elements “The same ink should often serve more than one graphical purpose” (139) Graphical element may carry data information and also perform a design function Element that locates or plots the data is the data measure, also pg. 144 “road stripes”
Multifunctioning Graphical Elements Data-Based Grids Grid reports directly on the data Sometimes it’s better to make the coordinate labels into the actual data points themselves. (this strategy eliminates the need to perform eye-work) example exampl Generally works better for smaller data sets
Multifunctioning Graphical Elements Puzzles and Hierarchy in Graphics Complexity of the elements can sometimes turn the graphic into a visual puzzle How to recognize: Graphic must be interpreted through verbal rather than visual process See page 153