erika.whillas.com » Tufte http://erika.whillas.com Erika Whillas is a Senior Web Producer based in New York Thu, 21 Jan 2010 15:28:15 +0000 http://wordpress.org/?v=2.8.6 en hourly 1 Theory of Data Graphics http://erika.whillas.com/theory-of-data-graphics/ http://erika.whillas.com/theory-of-data-graphics/#comments Mon, 04 May 2009 19:05:52 +0000 Erika http://erika.whillas.com/?p=246 Above all else show the data.
Data Ink is the non-erasable core of a graphic, the non-redundant ink arranged in response to variation in the numbers represented.

Data-ink ratio = _______data-ink__________
___________Total ink used to print the graphic

__________=    proportion of a graphic’s ink devoted to the non-redundant display of
____________data-information
__________=    1.0 – proportion of a graphic that can be erased without loss of
____________data-information

  • Maximize the data-ink ratio, within reason
  • Erase non-data-ink, within reason

Notes from The Visual Display of Quantitative Information by Edward R. Tufte

]]> http://erika.whillas.com/theory-of-data-graphics/feed/ 0 Sources of Graphical Integrity and Sophistication http://erika.whillas.com/sources-of-graphical-integrity-and-sophistication/ http://erika.whillas.com/sources-of-graphical-integrity-and-sophistication/#comments Mon, 04 May 2009 18:59:21 +0000 Erika http://erika.whillas.com/?p=244 Relational graphics are essential to competent statistical analysis since they confront statements about cause and effect with evidence, showing how one variable affects another.
Much of the world these days is observed and assessed quantitatively – and well-designed graphics are far more effective than words in showing such observations.

Notes from The Visual Display of Quantitative Information by Edward R. Tufte

]]> http://erika.whillas.com/sources-of-graphical-integrity-and-sophistication/feed/ 0 Visual Area and Numerical Measure http://erika.whillas.com/visual-area-and-numerical-measure/ http://erika.whillas.com/visual-area-and-numerical-measure/#comments Mon, 04 May 2009 18:58:33 +0000 Erika http://erika.whillas.com/?p=242 Many efforts using areas to show magnitudes make the mistake of varying both dimensions simultaneously in response to changes in one-dimensional data.
The use of two [or three] varying dimensions to show one-dimensional data is a weak and inefficient technique.
Principal: the number of information-carrying [variable] dimensions depicted should not exceed the number of dimensions in the data.
Context is Essential for Graphical Integrity Principal – Graphics must not quote data out of context
It is the special character of numbers that they have magnitude as well as an order; numbers measure quantity. Graphics can display the quantitative size of changes as well as their direction.

Notes from The Visual Display of Quantitative Information by Edward R. Tufte

]]> http://erika.whillas.com/visual-area-and-numerical-measure/feed/ 0 Design and Data Variation http://erika.whillas.com/design-and-data-variation/ http://erika.whillas.com/design-and-data-variation/#comments Mon, 04 May 2009 18:53:18 +0000 Erika http://erika.whillas.com/?p=238 Deception results from the incorrect extrapolation of visual expectations generated at one place on the graphic to other places.
The confounding of design variation with data variation over the surface of a graphic leads to ambiguity and deception, for the eye may mix up changes in the design with changes in the data.

Design principle – Show data variation, not design variation

Time-series Principal – In time-series displays of money, deflated and standardized units of monetary measurement are nearly always better than nominal units.

Notes from The Visual Display of Quantitative Information by Edward R. Tufte

]]> http://erika.whillas.com/design-and-data-variation/feed/ 0 To Ensure Graphical Integrity http://erika.whillas.com/to-ensure-graphical-integrity/ http://erika.whillas.com/to-ensure-graphical-integrity/#comments Mon, 04 May 2009 18:47:06 +0000 Erika http://erika.whillas.com/?p=231
  • The representation of numbers, as physically measured on the surface of the graphic itself, should be directly proportional to the numerical quantities represented.
  • Clear, detailed and thorough labeling should be used to defeat graphical distortion and ambiguity

    • Lie Factor =    size of effect shown in graphic
     __________size of effect in data

    Notes from The Visual Display of Quantitative Information by Edward R. Tufte

    ]]>     http://erika.whillas.com/to-ensure-graphical-integrity/feed/ 0     Principles of Graphical Excellence http://erika.whillas.com/principles-of-graphical-excellence/ http://erika.whillas.com/principles-of-graphical-excellence/#comments Mon, 04 May 2009 18:45:40 +0000 Erika http://erika.whillas.com/?p=229
  • Graphical Excellence is the well-designed presentation of interesting data – a matter of substance, of statistics and of design.
  • Graphical excellence consists of complex ideas communicated with clarity, precisions, and efficiency.
  • Graphical excellence is that which gives to the viewer the greatest number of ideas in the shortest time with the least ink in the smallest space.
  • Graphical excellence is nearly always multivariate.
  • Graphical excellence requires telling the truth about the data.

    • Notes from The Visual Display of Quantitative Information by Edward R. Tufte

    ]]>     http://erika.whillas.com/principles-of-graphical-excellence/feed/ 0     Data Graphics http://erika.whillas.com/data-graphics/ http://erika.whillas.com/data-graphics/#comments Mon, 04 May 2009 18:42:47 +0000 Erika http://erika.whillas.com/?p=226
  • Data Graphics visually display measured quantities by means of the combined use of points, lines, a coordinate system, numbers, symbols, words, shading and color.
  • Graphics are instruments for reasoning about quantitative information.
  • Graphical Excellence is the efficient communication of complex quantitative ideas.
  • Graphics ‘reveal’ data
  • For analyzing and communicating statistical information, well designed data graphics are usually the simplest and the most powerful method.
  • Graphics ‘reveal’ data
  • Statistical graphics, just like statistical calculations, are only as good as what goes into them.
  • The skills required for the use of abstract, non-representational pictures to show numbers are diverse – the visual-artistic, empirical-statistical, and the mathematical

    • Notes from The Visual Display of Quantitative Information by Edward R. Tufte

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