When I first reviewed it for RSS, I became a fan of van Belle's "Statistical
rules of thumb", if not totally agreeing with everything.
In the current discussion, I can recommend his Chapter 7: "Words, Tables and
Graphs" which is summed up in the very first section as "Use text for a few
numbers, tables for many numbers, graphs for complex relationships". I think
that I would go along with that.
Subsequent sections include "Never use a pie chart" and "Stacked bargraphs
are worse than bargraphs"! Whether or not you agree with them, a fair case
is argued in each case.
I haven't seen the second edition, but there is an associated website
www.vanbelle.org where you can post comments.
Quentin Burrell
Dr Quentin L Burrell
Isle of Man International Business School
The Nunnery
Old Castletown Road
Douglas
Isle of Man IM9 4EX
via United Kingdom
[log in to unmask]
www.ibs.ac.im
----- Original Message -----
From: "Zaloznik, Maja" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, March 20, 2009 1:05 PM
Subject: Re: pie charts
>
> almost without exeption, pie chart segments are labeled with their
> percentage values. that in itself is proof enough that it is an
> inefficient visualising technique, in addition to the literature already
> cited prooving that it is also ineffective.
> maja.
>
>
> ________________________________________
> From: email list for Radical Statistics [[log in to unmask]] On
> Behalf Of Michael Goller [[log in to unmask]]
> Sent: 20 March 2009 12:46
> To: [log in to unmask]
> Subject: Re: pie charts
>
> Dear Robert,
>
>> I don't think I've used pie charts, except perhaps when showing how
>> wealth is divided, where 'slices of the pie' make some sort of sense.
>> But I get the feeling from some of the exchanges (Jane Galbraith for
>> example) that pie charts are not much loved by statisticians. Is
>> there a technical reason for this? Whilst I don't find them very
>> useful, the kids are obviously drawing pie charts at school - on
>> every topic - what should we say to teachers if we wish to discourage
>> this?
>
> The following link might be interesting for you:
> http://seedmagazine.com/content/article/getting_past_the_pie_chart/
>
> "Playfair rightly intuited that visual representations of data can
> enable people to make comparisons more easily. Many psychoperceptual
> studies have explored the human mind’s aptitude for gleaning
> information from pictures. Unfortunately, the pie chart incorporates
> tasks that we humans systematically fail to perform accurately, all
> those exercises that come at the bottom of the hierarchy of perceptual
> tasks, formalized by Cleveland in a landmark 1984 paper. So although
> we’re good at comparing linear distances along a scale — judging which
> of two lines is longer, a task used in bar graphs — and we’re even
> better at judging the position of points along a scale, pie charts
> don’t bring those skills to bear. They do ask us compare angles, but we
> tend to underestimate acute angles, overestimate obtuse angles, and
> take horizontally bisected angles as much larger than their vertical
> counterparts. The problems worsen when we’re asked to judge area and
> volume: Regular as clockwork, we overestimate the size of smaller
> objects and underestimate the size of larger ones, to a much greater
> degree with volume than with area."
>
> (Source:
> Understanding the shortcomings of the pie chart can help us
> make sense of and improve the emerging scientific aesthetic of the 21st
> century. Getting Past the Pie Chart
> Universe in 2009 / by Veronique Greenwood / February 18, 2009)
>
> Best wishes
> Micha
> --
> "I keep saying the sexy job in the next ten years will be
> statisticians. People think I’m joking, but who would’ve guessed that
> computer engineers would’ve been the sexy job of the 1990s?" - Hal
> Varian, The McKinsey Quarterly, January 2009
>
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