A1-KetrinaYim
From CS294-10 Visualization Fa08
Contents |
A Good Visualization
Source: "Olympic Science". Popular Mechanics, 185(8). August 2008, p. 68.
Explanation:
This illustration depicts the stages of an Olympic pole vault, as well as the various components of the pole vault area. The fact that the entire vault is displayed frame-by-frame visually conveys the order in which the four steps takes place and the role that each step plays in achieving a successful vault. Each step is also clearly indicated by a number placed directly below the frame at which the step begins. The yellow box surrounding the image of the vault effectively frames the image area, yet a small part of the picture lies outside of the box to unite the illustration with the surrounding text. The visualization also features a small diagram displaying the internal structure and materials of the modern vaulting pole, following the same "yellow and white with black lines" color theme to clearly show that it and the vault diagram go together.
Deconstruction:
The visualization conceptually portrays the entire vault process as a sequence of 12 images. The sequence reveals the ordinal nature of the data. The human figures are drawn in thick black outlines with some black fill, making them stand out and leading the viewer to focus on the poses. At the same time, the poles are drawn as dark gray, so that it is easy to visually separate the vaulter from the pole should one be more interested in how the pole bends during the vault rather than how the vaulter's body is shaped.
The the vaulter's distance (as well as the passage of time) is encoded as X-position and altitude is encoded as Y-position in the image, giving the impression that one is looking from the sidelines. The side view also allows the sequence to be spaced out to minimize overlaps. However, because the diagram is meant to be conceptual, there are no numbered axes for the X-Y position so that a viewer need not be concerned about the actual distance or height the vaulter travels. Also, with the exception of the leftmost image, the image sequence depicts the four steps of a vault, where the beginning of each step is labeled with an ordinal number directly under the image of the vaulter. The steps are described by short numbered passages directly below the image sequence, so one can easily correlate the number labels with the passages. Five black boxes with text nominally indicate the four components of the area, the runway, box, pit, and crossbar, and the current record of 20' 1.75". A large red arrow on the left indicates the vaulter's direction, though it is unnecessary as there are already several signs showing that the diagram must be read from left to right, such as the numbering and the fact that the vaulter is clearly depicted as running towards the right.
The accompanying image of the vaulting pole's structure is also conceptual, showing the three components that make up the pole. Differing textures and colors serve to distinguish each component. Also, each component is shown as a cylinder of different size, so the layer each occupies is encoded in the cylinders' ordinal arrangement.
A Bad Visualization
Source: Gomez, Chertoprud & Morales-Serna. "New Species of Diarthrodes from Mexico and Vietnam". Cahiers de Biologie Marine, 49(2). 2008, p. 133.
Explanation:
This image depicts the dorsal(A) and ventral(B) views of a urosome (abdomen) belonging the female specimen of a newly discovered microscopic crustacean known as Diarthrodes hexasetosus. (C) and (D) illustrate the dorsal and ventral views, respectively, of the crustacean's left ramus, an appendage found at the animal's posterior. (C) also points out the seven setae, or bristles, found on the ramus. The scale bar on the left is 100 micrometers for (A) and (B), and 50 micrometers for (C) and (D). The central flaw of this illustration comes from the fact that its meaning is heavily dependent on the paper. Without the caption accompanying the image, the letters mean nothing. And without having read the section of the paper referring to the image, which also happens to be on a different page, the roman numerals labeling the setae also have no apparent significance.
Deconstruction:
The diagram is primarily nominal data, being composed of 4 images with letters used to label each image to indicate what it represents. The close packing of the images affects the letters' positions, so the viewer must look in a different place each time to find the label for an image. Also, the lettered labels dismiss the connection between the whole animal and the left ramus, so that the viewer does not immediately realize that (C) and (D) represent a section of (A) and (B), respectively. The visualization is clearly meant to show what the species' urosome looks like, because each image is quite detailed in showing both the ventral and dorsal views. Less clear is the motivation for labeling the nominal data of the 7 setae with Roman numerals, since the significance of the Roman numerals is explained only in the body of the article.
The scale bar on the left offers the viewer a method of determining the size of the creature, and so the size of the images can be said to present the creature's typical length and width, as well as the length and width of a typical ramus (a total of 8 quantitative ratio values). However, it is not immediately apparent what the scale bar represents, because there are no numbers alongside the bar. It could be mistaken as an extraneous line accidentally added by the printer. The fact that the bar simultaneously represents 100 micrometers for the urosome images and 50 micrometers for the ramus images only complicates matters. At first glance, one might assume the ramus was at least 100 micrometers in length, only to be immediately contradicted by seeing how small the ramus is in the urosome image.
Reconstruction:
Several edits were made to the original visualization to make it easier to read and to reduce reliance upon a captioned explanation. First, I replaced the letter labels with word labels indicating if the images were of dorsal or ventral views. Second, I made the ramus images an inset of the urosome images, as well as giving each set a separate and labeled scale bar, to make the diagram less crowded-looking and to clarify that the ramus is part of the urosome. Third, I made it clear that the Roman numerals referred to setae. Though one must still read the paper for word descriptions of the setae, the Roman numerals seem less mysterious. Finally, I added color to the visualization to make it easier to distinguish the images from the labels and lines, but not so much color that the eye is distracted from the images.
