Hi Richard, > I apologize that this is off-topic. I am seeking information on > perception of graphical data, in an effort to improve the plots I > produce. Would anyone point me to literature reviews in this area? (Or > keywords to try on google?) Is this located somewhere near cognitive > science, psychology, human factors research?
Probably the best place to start on these general issues, are a couple of papers by Cleveland: @article{cleveland:1987, Author = {Cleveland, William and McGill, Robert}, Journal = {Journal of the Royal Statistical Society. Series A (General)}, Number = {3}, Pages = {192-229}, Title = {Graphical Perception: The Visual Decoding of Quantitative Information on Graphical Displays of Data}, Volume = {150}, Year = {1987}} @article{cleveland:1984, Author = {Cleveland, William S. and McGill, M. E.}, Journal = {Journal of the American Statistical Association}, Number = 387, Pages = {531-554}, Title = {Graphical Perception: Theory, Experimentation and Application to the Development of Graphical Methods.}, Volume = 79, Year = 1984} For colour in particular, I like Ross Ihaka's introduction to the subject: @inproceedings{ihaka:2003, Author = {Ihaka, Ross}, Booktitle = {Proceedings of the 3rd International Workshop on Distributed Statistical Computing (DSC 2003)}, Title = {Colour for Presentation Graphics}, Year = {2003}} and also see colorbrewer.org > Scatter plots of microarray data often attempt to represent thousands or > tens of thousands of points, but all I read from them are density and > distribution --- the gene names cannot be shown. At what point, would a > sunflowerplot-like display or a smooth gradient be better? When two > data points drawn as 50% gray disks are small and tangent, are they > perceptually equivalent to a single, 100% black disk? Or a 50% gray > disk with twice the area? What problems are known about plotting with > disks --- do viewers use the area or the diameter (or neither) to gauge > weight? I think many of these are still research topics. Two (of many) places to start are: @article{huang:1997, Author = {Huang, Chisheng and McDonald, John Alan and Stuetzle, Werner}, Journal = {Journal of Computational and Graphical Statistics}, Pages = {383--396}, Title = {Variable resolution bivariate plots}, Volume = {6}, Year = {1997}} @article{carr:1987, Author = {Carr, D. B. and Littlefield, R. J. and Nicholson, W. L. and Littlefield, J. S.}, Journal = {Journal of the American Statistical Association}, Number = {398}, Pages = {424-436}, Title = {Scatterplot Matrix Techniques for Large N}, Volume = {82}, Year = {1987}} > As you can tell, I'm a non-expert, mixing issues of data interpretation, > visual perception, graphic representation. Previously, I didn't have > the flexibility of R's graphics, so I didn't need to think so much. > I've read some of Edward S. Tufte's books, but found them more > qualitative than quantitative. More quantitative approaches are Cleveland's, Bertin's and Wilkinson's: @book{cleveland:1993, Author = {Cleveland, William}, Publisher = {Hobart Press}, Title = {Visualizing data}, Year = {1993}} @book{cleveland:1994, Author = {Cleveland, William}, Publisher = {Hobart Press}, Title = {The Elements of Graphing Data}, Year = {1994}} @book{chambers:1983, Author = {Chambers, John and Cleveland, William and Kleiner, Beat and Tukey, Paul}, Publisher = {Wadsworth}, Title = {Graphical methods for data analysis}, Year = {1983}} @book{bertin:1983, Address = {Madison, WI}, Author = {Bertin, Jacques}, Publisher = {University of Wisconsin Press}, Title = {Semiology of Graphics}, Year = {1983}} @book{wilkinson:2006, Author = {Wilkinson, Leland}, Publisher = {Springer}, Series = {Statistics and Computing}, Title = {The Grammar of Graphics}, Year = {2005}} Hope this gets you started! Hadley -- http://had.co.nz/ ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.