Worth a Thousand Words
Raw data, statistical analysis, standard forms of graphing the result… sometimes observing these obscures what is really interesting about the information at hand. A clever or novel ways of visualizing data may, on the other hand, uncover phenomena that just jump at us from the image: “Wow! This is interesting!”
In other cases, while statistical analysis itself discovers the hidden phenomena, what it really needs is a powerful image to drive the point home. One such recent PLoS ONE study exemplifies this well. The article Mapping Change in Large Networks by Martin Rosvall and Carl T. Bergstrom from the Department of Biology at the University of Washington, Seattle, analyzes thousands of citations of scientific articles and uses novel mathematical methods to discover nodes and networks in the citation data. What really jumps out from the images is how different scientific disciplines experience phase-changes: two disciplines fuse into one, or one discipline gives rise to a daughter sub-discipline which later becomes an independent discipline:
Most noteworthy result from the study is the demonstration that neuroscience only became an independent discipline within the last decade or so:
As the authors say in the Abstract:
Change is a fundamental ingredient of interaction patterns in biology, technology, the economy, and science itself: Interactions within and between organisms change; transportation patterns by air, land, and sea all change; the global financial flow changes; and the frontiers of scientific research change. Networks and clustering methods have become important tools to comprehend instances of these large-scale structures, but without methods to distinguish between real trends and noisy data, these approaches are not useful for studying how networks change. Only if we can assign significance to the partitioning of single networks can we distinguish meaningful structural changes from random fluctuations. Here we show that bootstrap resampling accompanied by significance clustering provides a solution to this problem. To connect changing structures with the changing function of networks, we highlight and summarize the significant structural changes with alluvial diagrams and realize de Solla Price’s vision of mapping change in science: studying the citation pattern between about 7000 scientific journals over the past decade, we find that neuroscience has transformed from an interdisciplinary specialty to a mature and stand-alone discipline.
And the nifty visualization makes their point very clear.