A few days ago the following screenshot on Business Objects’ website was brought to my attention:
I was pleased to see sparklines and bullet graphs in this example, because they can work quite effectively on dashboards, but I was bothered by several problems with the implementation. Being short of time, I asked Bryan Pierce, who works with me, to critique the dashboard, which he has done below.
This screenshot is intended to demonstrate a new add-on for BusinessObjects XI called BI Annotator. It was the dashboard used to exhibit the add-on, however, and not the add-on itself, which caught my eye. Specifically, the column labeled “Current Performance.” Although this dashboard has multiple problems, such as column headers that are not aligned to match their data, the primary problem involves the implementation of the bullet graphs (that is, the linear bar-like graphs in the “Current Performance” column). Bullet graphs were invented by Stephen as a compact, data-rich, and efficient alternative to gauges on a dashboard. Below is an example of a bullet graph with labeled parts.
When Stephen created bullet graphs he gave an open invitation to software vendors to implement them and has since freely provided a design specification to anyone who is interested. As you can see, Business Objects has attempted to do this, but with limited success. They realized that bullet graphs can serve a useful purpose, but they haven’t taken the time to understand why they work and to design them according to that understanding.
The first problem with the bullet graphs in this example is that they lack a quantitative scale. Without a labeled scale you cannot make quantitative judgments about the bars. You can make qualitative judgments of “Bad,” “Fair,” and “Good,” based on the color-coding of the bars, the circle icons to the right of the bullet graphs, and background color in the bullet graphs, but to determine a quantitative value you must rely on the percentage column to the right, which tells you nothing about the values associated with the ranges of bad, fair, and good.
On a closer comparison of the percentages to the bar lengths, one might assume that Business Objects intentionally left off the quantitative scale to hide another problem: The bars do not have a zero baseline. It appears that the quantitative scale starts at approximately 80%. This creates two problems. First, it exaggerates the actual differences between the bar lengths. This problem can be seen by comparing the first two bars, Bluetooth and Core CDMA. Although the Core CDMA bar appears to be about twice the length of the Bluetooth bar, it represents a value that is only 11% greater. Second, what happens if a value is less than 80%? You might assume that the non-zero baseline would automatically be set to just below the lowest value of the bars, but, as a quick glance at the PTOM bullet graph will tell you, that assumption would be wrong. The PTOM graph represents a value of 0% and therefore has no bar at all. This value is 90 percentage points less than the next lowest value, but the difference in bar length is only about 1/5th of the difference in bar length between the second lowest value and the highest value (a value difference of 46%). Because Business Objects used a non-zero baseline and then implemented it sloppily, the differences in length between the bars are not only exaggerated, they are also inconsistent.
My next problem with the bullet graphs involves the use of color. As mentioned before, notice how the qualitative values of “Bad,” “Fair,” and “Good” have been tri-encoded on the bullet graphs. These values are encoded as the colors of the bars and circle icons (red for “Bad,” yellow for “Fair,” and green for “Good”), as well as in the intensity of the background color (dark gray, medium gray, and light gray for the respective qualitative values). One problem with this approach is that 10% of men and 1% of women are color blind, and most of them cannot distinguish green from red. Second, color coding has been overused, undermining its ability to function effectively. Often, when people over use color in a dashboard, they do so with the best of intentions. They believe that by color-coding everything, they will make the display easier to comprehend as a whole. Unfortunately, however, when everything stands out, nothing does. Because of this, bright, intense colors should be reserved only for highlighting objects that demand our attention. Everything else should be muted. Grays and soft colors like those found in nature work well. Below is a series of bullet graphs that Stephen designed for use as a section of a larger call center dashboard, which provide an example of appropriate color use.
The different shades of gray in the background of the bullet graphs provide subtle qualitative encoding while color is used only for those measures that demand attention. It’s easier to look at these gray graphs than the brightly colored graphs in the Business Objects example and the items of most importance jump out more quickly and clearly. It also functions well for those who are color blind.
Another feature that Business Objects’ bullet graphs lack is an adequately labeled comparative measure. A comparative measure gives the bullet graph meaningful context. For instance, sales of $24.3 million are not very meaningful until you know how that compares to some other measure such as the target, last year’s sales, or average sales. In this case, we might assume that the little white bar located between the medium gray and light gray background areas is the comparative measure because it appears to be located at about the 100% mark (although again, this must be approximated because there is no quantitative scale). If we assume that this is the case, then we’re still left without appropriate context because the comparative measure is not defined. If it represents a target, 100% might be good, but if it represents last year’s performance, 100% might not be good: 100% of last year’s performance isn’t so good if you were expecting 10% growth. The comparative measures need to be adequately labeled and they should be slightly more prominent, so that they’re easier to spot. Additionally, they shouldn’t be built into the background, because there are bound to be cases where the breakpoint between “Fair” and “Good” and the target are different. Or at least, there should be.
But, maybe that’s the point. Perhaps, Business Objects is just trying to be “good enough” to turn a profit, instead of making an effort to excel. So often, software vendors choose the easy route, giving people more of the visual fluff they’re so used to, instead of creating products that actually function well, based on a keen understanding of what works and why.