The Dow Jones Animated Parallel Multiverse: Visualization Challenge Second Prize Winner

At any instant in time, the stockmarket can be thought of as a many-dimensional space, with the dimensions being quantities such as: the price of each stock, the volume traded, the number of trades, the number and volume of bid/ask orders, and so on. For the 30 stocks in the Dow Jones average, considering just the price and volume of trades gives a 60-dimensional space. Most direct visualisation techniques can only deal with low dimensional data, that is, up to about 10 dimensions (3 spatial, 1 temporal, plus some variable “visual attributes” such as colour, texture, glyph size/shape). Thus a technique is needed to map this high dimensional space down to a low dimensional one for visualisation. Parallel Coordinate Plots are a method of mapping such high dimensional spaces to a low dimensional visualisation. Rather than plotting each point in space as the intersection of coordinates on orthogonal axes, parallel coordinate plots draw the axes as a set of parallel lines. A point in the many-dimensional space is then represented as a line joining the corresponding values on each axis. This visualisation uses an animated parallel coordinate plot to directly show the evolution of the Dow Jones Index stocks during the week of 29 September 2008 to 3 October 2008. The animation, which runs for about 1½ minutes, is similar to a time-lapse video, with each frame showing the state of “multidimensional universe” of Dow Jones stocks during one minute of the week (1500 times faster than real-time). The primary data shown is the change in price of stocks traded, as a percentage relative to its price at the start of the week. The parallel coordinate plot is augmented in several ways. First, the relative volume of the trades is shown relative to the maximum per-minute trade volume (per stock). These volumes are shown as vertical segments along each stock's axis, with maximum trade volume being represented by a segment half the height of the plot. Second, the Reuters news reports are shown as brief yellow highlights of the relevant stocks' axis which quickly fade, along with display of the headline vertically along the axis. Finally, the average trade price (and 2 standard deviations) is shown as a purple segment along each axis, providing some overall context for the movement of the stocks. One “free parameter” of parallel coordinate plots is the axis ordering. This visualisation shows the stocks ordered by their (decreasing) relative price change at the end of the week. This allows the viewer to follow the progression of the stocks toward their ultimate “position” in the market at the week's end. Other orderings are possible, for example, average trade price, trade price volatility, total trade volume, total trade value, measures of company size, etc. The data was processed using the awk language, which generated data and scripts for visualisation using gnuplot. The individual frame images were then converted into animations using transcode.