Thursday, October 10, 2013

More connected scatter plot fun

A while ago, I wrote about connected scatter plots. This graphic form is quite unusual in the news, but it may come in handy to display covariation. Today, The New York Times has published this —the print version of the graphic is quite large, by the way; I'm glad that the Times' graphics desk is still willing to challenge its more traditional readers a bit:

As I've discussed before, it's reasonable to argue that two stacked line charts would be equally —or more— effective and intuitive than the connected scatter plot. If you are a visualization researcher in need of a topic to study, it'd be really interesting to conduct an experiment comparing how easily readers interpret both graphic forms. I'm in favor of the connected scatter plot in certain cases, but I'd like to have some evidence either to confirm or nullify my hunch.


  1. i'm fairly sure that you know this, but such diagrams are fairly common in technical science and known as "phase diagrams" or "phase portrait" ( ) - since they convey two (interdependent) variables (e.g. temperature & pressure) plus time by "bending" the time-line.
    in "stable" (or ideal) systems they allow for identification of "critical" points (i.e. points of equilibrium, or bifurcation, etc.).

  2. Thanks so much for your comment. Yes, I knew about phase diagrams, but I've always wondered if it's correct to use that term for any graph of this kind, regardless of the data it encodes. It has a precise meaning in the physical sciences and Mathematics