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Comment by jacobolus | Hacker News Reader

> But your nice professional looking documents can be ruined because you insert the wrong type of figures.

Example A of the wrong type of figure for any possible context: 3-dimensional pie charts.

Most 3D plots are terrible because there's an inherent loss of information when flattened onto a 2D screen or piece of paper. Not only that, but you can't read off absolute values from a 3D chart without every point being labelled. They're also great if you want to mislead (e.g. by rotating them).

Most pie charts are terrible as well, it's very hard to compare the sizes of slices. There's a good piece on pie charts at http://www.businessinsider.com/pie-charts-are-the-worst-2013... with a quote from Edward Tufte: "Pie chart users deserve same suspicion+skepticism as those who mix up its/it's, there/their.To compare,use little table, sentence, not pies."

The combination, especially when used for a publication, is just a disaster.

And the fact that the 3rd dimension adds no information and instead adds perspective distortion.

If your audience like/expect/demand pie charts I find donut charts to be a nice alternative. They do essentially the same thing but prevent people from trying to interpret the area of wedges.

http://www.datavizcatalogue.com/methods/donut_chart.html

Darrell Huff, in his "How to Lie With Statistics" says 3-d charts should never be used, since you can easily lie with them (by rotating it, e.g,)

Yes, that is a good point -- it does include the percentages at least.

Not necessarily. For instance, some academic journals are on their way to allow interactive 3d plots in the pdf files [1]

[1] http://journals.plos.org/plosone/article?id=10.1371/journal....

Which they hopefully won't allow to be used for 3d pie charts, but visualizations where being 3D is actually useful.

3D plots can useful when the data is intrinsically 3D. But forcing a 3D plot on 2D data, like a pie chart, makes it hard for a viewer to develop an intuition for the data.

Fair point, I overlooked the "pie" part of the chart argument. My comment was originally intended to go as a reply to oriettaxx's post.

AFAIK the only viewer that supports interactive 3D in pdf is Adobe Reader. At this point should we stick to the pdf format? Obviously interactive 3D is not meant for printing anyway. Some open access journals publish in html format too, 3D plots can work there better.

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