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The Visual Display of Quantitative Information. Leading authority: Edward R. Tufte. History of Graphical Development. First geographic maps were drawn on clay tablets.17th Century: combined map skills and statistical skills to construct maps.Trade winds and monsoons on a world map.Chart pattern
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2. The Visual Display of Quantitative Information Leading authority: Edward R. Tufte
3. History of Graphical Development First geographic maps were drawn on clay tablets.
17th Century: combined map skills and statistical skills to construct maps.
Trade winds and monsoons on a world map.
Chart patterns of disease.
Later sophistication showed distribution of 1.3 million galaxies.
First geographic maps were drawn on clay tablets.
The 17th century combined map skills and statistical skills to construct maps.
One of the first data maps was Halleys 1686 chart showing trade winds and monsoons
on a world map.
Early use was to chart patterns of disease. Dr. John Snow plotted deaths from cholera in central London for September 1854. He found the most deaths at eleven water pumps, and then had those water pump handles removed, which had taken over 500 people.
Later sophistical showed distribution of 1.3 million galaxies, but the producers were cautiuous to observe that the visual impression may be misleading: there is no linearity patterns in random noise.
First geographic maps were drawn on clay tablets.
The 17th century combined map skills and statistical skills to construct maps.
One of the first data maps was Halleys 1686 chart showing trade winds and monsoons
on a world map.
Early use was to chart patterns of disease. Dr. John Snow plotted deaths from cholera in central London for September 1854. He found the most deaths at eleven water pumps, and then had those water pump handles removed, which had taken over 500 people.
Later sophistical showed distribution of 1.3 million galaxies, but the producers were cautiuous to observe that the visual impression may be misleading: there is no linearity patterns in random noise.
4. Graphical excellence consists of the efficient communication of complex quantitative ideas.
7. At their best, graphics are instruments for reasoning about quantitative information.
10. Design is choice.
26. Principles of Graphical Excellence Well designed presentation of data that provides:
Substance
Statistics
Design
Communicates complex ideas with clarity, precision and efficiency
Gives the largest number of ideas in the most efficient manner
Almost always involves several dimensions
Requires telling the truth about the data
27. Data-Ink Ratio Data information
Total ink used to print the graphic Data-ink ratio = data information divided by the total ink used to print the graphic. Non data information = gridmarks, ticks, frame, clip art.Data-ink ratio = data information divided by the total ink used to print the graphic. Non data information = gridmarks, ticks, frame, clip art.
28. Much of twentieth-century thinking about statistical graphics has been preoccupied with the question of how some amateurish chart might fool a naive viewer.
29. Using chart junk
No relative basis
In comparing data
Batches
Compressing the
Vertical axis
No zero point on the
Vertical axis Errors in Presenting Data
30. Chart Junk In time-series displays of money, either present the graphics in proportion to the change, or show nominal units.In time-series displays of money, either present the graphics in proportion to the change, or show nominal units.
31. Lie Factor Size of effect shown in graphic
Size of effect in data Does the graphic do a reasonable job of accurately representing the underlying numbers? Is the graphic distorted in relation to the sequential changes in the data?Does the graphic do a reasonable job of accurately representing the underlying numbers? Is the graphic distorted in relation to the sequential changes in the data?
32. No Relative Basis
33. Compressing Vertical Axis The number of information-carrying (variable) dimensions depicted should not exceed the number of dimensions in the data.The number of information-carrying (variable) dimensions depicted should not exceed the number of dimensions in the data.
34. No Zero Point on Vertical Axis
35. No Zero Point on Vertical Axis Always show zero on your chart, then indicate the level of beginning measurement.Always show zero on your chart, then indicate the level of beginning measurement.
36. Main defense of the lying graphic.... Well, at least it was approximately correct, we were just trying to show the general direction of change.
39. There remain, however, many other consideration in the design of statistical graphics not only of efficiency, but also of complexity, structure, density, and even beauty.