Oracle Corporation takes its name from the treasured advice-givers of ancient Greece. Its name is ironic at times, however, when its advice is far from sage. When it comes to data visualization, and dashboard design in particular, Oracle gives some downright awful advice.
I received an email from one of my readers who uses Oracle’s OBIEE tool to develop applications for his customers. He attached the following graph as an example of what Oracle teaches people when they attend the online course “Oracle BI Enterprise Edition – Build Good Dashboards”:
Based on this graph, I’m guessing that Oracle now outsources the development of its courses to the primate house of the local zoo. Although I haven’t seen the course myself, I’m told that this graph is typical. If this is what a leading Business Intelligence software vendor considers an effective way to display data, it’s no wonder that people are frustrated with the industry.
Almost every aspect of this graph fails miserably.
- It has been complicated by a 3-D rendering of the plot area and the bars (or tubes in this case), which does nothing but make it harder to interpret the values. Notice that the quantitative scale for “Dollars” and “Year Ago Dollars” on the left axis is aligned with the front of the graph, but the scale for “Forecasted Dollars” and “Forecasted units” on the right is aligned with the back of the graph.
- I assume that the quantitative scale on the left is for dollars and the one on the right is for units. If this is the case, however, the title that appears on the right-“Forecasted Dollars, Forecasted Units”-is incorrect.
- A dual-scaled graph—one quantitative scale on the left for dollars and one on the right for units—should usually be avoided, especially on dashboards, because it can be confusing and misleading. For example, notice that the forecasted units line intersects the dollars’ bars, which would naturally incline anyone viewing the graph to compare their magnitudes, yet this would be entirely meaningless, because magnitude comparisons can’t be made between them when they have entirely different scales and units of measure.
- Forecasted units would not be useful on this graph without including actual units, which has apparently been forgotten.
- Lines representing “Forecasted Dollars” and “Forecasted Units” have been used to connect values per region, which makes no sense. The patterns formed by the lines are completely arbitrary and could be changed by sorting the regions in a different order.
- The lines have large, clutter-inducing data points along them.
- The lines appear to have some sort of drop shadow or lighting effect, which makes it look as if there are four lines rather than two.
- “Dollars” for the current year and “Year Ago Dollars” are meant to be compared, not summed. By using stacked bars rather than placing separate bars side by side for the current year’s dollars and the previous year’s dollars, the comparison is difficult to make. The bars as a whole, consisting of both years stacked on one another, represent a sum that is useless in this situation.
- Given the fact that the X-axis has the title “Region”, there is no reason to clutter the graph by including “REGION” in each of the labels.
- The prominent vertical grid lines that separate the regions are unnecessary, resulting in clutter.
- The tick marks along both vertical axes are unnecessary, because gridlines appear in the graph at the same positions.
- The minor tick marks on the right-hand vertical axes are darker than the major tick marks.
- The positions of the two Y-axis titles are inconsistent, resulting in a sloppy appearance.
It is as if the person who created this “Good Dashboards” example of a graph did everything possible to make it as ineffective as possible.
How can a vendor that claims to understand data and presumes to teach people best practices in its use know so little? Oracle, you should be embarrassed.