A1-Jih-YinChen
From CS294-10 Visualization Fa07
[edit] Good Visualization
This visualization for the US presidential polls is taken from Newsweek. The graphics are clear and informative. The lines and dots are marked with different colors, which makes it clear to compare the supports of different candidates. Another good thing is the use of lines (looks like linear regression) rather than data dots. The lines make it easy and clean to recognize each candidate's support in a single graph, without mixing up with the dots. And the lines could also visualize the poll trend. In addition, it is good to make the color of grids as light gray. This clearly segments the graph with time and values, while not obscuring the actually data in the graph.
It's also good to have additional graphs for the polls in individual states, as shown in the smaller graphs in the right. The minor problem for the small graphs is that the date information is not clear enough. We don't know whether the grids are by month, day, or anything else. It'll be better to put the date in the bottom of the small graphs.
[edit] Bad Visualization
This visualization for the stock data of the five companies is taken from San Jose Mercury News. Although there's no problem if we look at each stock chart separately, it's misleading when these charts are put together. As these charts are aligned next to each other, the viewers would tend to compare the stock trend of these companies. However, the problem comes from values of y-axis: the scale and range of the stock values for each chart are not consistent. This makes it misleading when we compare the stock values based on these curves. For example, the range of stock values in the LSI chart is from $4 to $10, but that of PDL Biopharma chart is from $10 to $40. If we compare the two companies based on the curve itself, we may have the impression that the two companies are similar in stock values, while they are actually very different. Such design variation is not a good style of visualization. As readers rely heavily on the visualization to compare the stock values, the scale and range of the charts should be consistent so as to show what the data really is.
