From Visualization Sp06

Good Visualization

Maxim Magazine, September 2005. "The Lost Boys", pg.120

1. Explanation

The first visualization shows the story of 2 boys, Josh and Troy, who were lost at sea for almost a week. After two days of futile searching, the Coast Guard suspended their search because their calculations believed them to be dead. Thus Josh and Troy braved the elements and Nature for 6 days before by a stroke of luck a fisherman named Captain Ben DeGutis spotted and rescued them.

What this visualization shows not only the boy's path, but also that the Coast Guard searched in a very limited area. This visualization enchances the reader's understanding of the boys' plight; for those who did not read the article, it serve as a fast and efficient way to learn what had happened to them. It is intended for readers of Maxim Magazine.

2. Deconstruction

The boats in the picture depicts the boy's appoximate location each day. The numbers also give reference to with subimage associated with it. This is a quantitative data model. The visual cues used here are position and orientation for the boats. The colored lines are also used to "contain" the Coast Guard search area. The color of the water was also used in an ordinal way; as the boys got further away from shore, the bluer the ocean became.

3. Critique

I believe this a good visualization because it captured the whole story in one single visualization. It also has a good use of space; each subimage helped portray this story even further as it shows what happened on each day. On the other hand, if the images were not there, the visualization would not be as effective since there would be much wasted ink showing the inland and ocean (which were not pertinent to the story). This visualization also shows that perhaps the Coast Guard had suspended the search too early; according to the story, "local boaters who knew the coastal waters began to question the grid. Some believe had most likely drifted up the coast instead of down, yet the grid ran 20 miles farther to the south than to the north." Looking at the visualization, it is clearly shown that the Coast Guard had a made mistake in the calculations.

To improve the visualization I would include when the Coast Guard suspended their search and perhaps which way the ocean currents moved. Also an indication of scale would have been nice.

Bad Visualization

Scientific American, February 2006. "Owning the Stuff of Life, pgs. 78-79

1. Explanation

This second visualization contains 24 bar graphs depicting how often genes are patented for each chromosome. The University of California (which currently holds the most), the U.S. Government and Stanford are some of the establishments that hold these patents. The intended audience is the readers of Scientific American, or usually those who are interested in intellectual property, biomedical research or laws/policy concerning biotech.

2. Deconstruction

This visualization uses the concept of "small multiples" in an attempt to present the information clearly. For each graph (which symbolizes a chromosome), a bar represents how many patents have occured for each chromosome segment (which may contain multiple genes). The color of the bars represent the same value as the height of the bar (quantitive data type). The "chromosomes" are shaded to differentiate segments(nominal data type).

3. Critique

This visualization presents much inefficiency as Professor Few pointed out in his lecture. First off, each bar graph is in 3d; this is simply "chartjunk" (Tufte) and reduces the data::ink ratio. Furthermore, each graph is so small that it’s hard to delineate any real information from it. There is simply not enough space between each bar! Another problem is that too much time is need to switch back and forth between the legend and the graph; like Few says, the purpose of a visualization is to give an alternative for mental images, which I believe this fails at.

This graph is also misleading because it states that it "offers an indication of how often genes have been patented in the U.S." This causes you to believe that each segement represents a gene, when in fact, "each colored bar represents the number of patients in a given segment of a chromosome, which can contain several genes". As a reader, I would have liked to been able to compare patents on individual genes, not just chromosome segements.

One positive that this visualization has is that it upholds the small multiples design principle as mentioned above.

Even if my criticism came because I am not included in the targeted audience (which may be those who work in the biotech field and thus would have more background knowledge), I still feel that one cannot extract anything useful from the graphs. In fact, the totals (genes/patents) may be the only useful information!

A couple changes I would make would increasing the size of the each graph and simplifying it into 2D. Also, label the horizontal and vertical axiis so the graph analyzation is easier and remove the legend. It would also make each graph easier to read if the chromosome segements were ordered by number of patents held instead of their acutal positions (sort by bar height). If that is not possible, I would rather just go with a table format. Finally, organize each graph/table to show data for each individual gene.

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