In-Reply-To: <9804061020.AA13815@attunga.stats.adelaide.edu.au> Date: Mon, 06 Apr 1998 14:14:45 +0100 (BST) From: (Ted Harding) <Ted.Harding@nessie.mcc.ac.uk> To: Bill Venables <wvenable@attunga.stats.adelaide.edu.au> Subject: Re: R-beta: CI for median in funtion boxplot Martin Maechler <maechler@stat.math.ethz.ch> On 06-Apr-98 Bill Venables wrote: > > But why do people still look at boxplots so much, and why do they > spend so much time and technology on them? It really puzzles me. > With all the good work done in recent years on bandwidth > selection, why don't we communicate this kind of information, > between ourselves at least, with kernel density estimates more? > They could be embellished with a few reference percentiles, of > course, but to me they convey a whole lot more than boxplots. It > can't be very long before, like pie charts, boxplots are reserved > for politicians, advertising agents and others of their kind. > > > I don't know the exact history; in any case, John Tukey > > devised the boxplot, including the notches, and ``1.58 is THE > > number''. Like many early Tukey schemes, the boxplot was devised in days when most people only had line-printer output readily available. If you think about it, the boxplot can be drawn (to within character-width resolution) using basic ASCII symbols like - + | on a lineprinter/dumb terminal. "Experimental Data Analysis was written in 1976! The same is true for stem-and-leaf diagrams and the like. And very effective, too, for that medium. Tukey's graphical tricks were, for many people, the first experience they had of the comprehensible display of statistical summary data and I remember the furious eagerness with which they were accepted in groups whom more academic statisticians had previously regarded as, for practical purposes, out of reach; and tribute must be paid to pioneering teachers like the late Cathie Marsh who saw these methods as the bridge by which true understanding of data could be brought to them. As to why people still look at them, well, <cynical>old habits die hard, and something which works to your satisfaction is a better ploy than adapting to something new which may require unknown effort which you are not sure might be well spent</cynical>, but Bill's point, essentially that modern display technology can greatly improve on this without stressing the learner, seems good. (I still wonder a bit, though, whether someone used to a boxplot would readily derive the same information from a kernel density estimate without considerable practice). Best wishes to all, Ted. -------------------------------------------------------------------- E-Mail: (Ted Harding) <Ted.Harding@nessie.mcc.ac.uk> Date: 06-Apr-98 Time: 14:14:45 -------------------------------------------------------------------- -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-help-request@stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._