The term Data Visualization loosely refers to the techniques used to communicate data or information by creating visual objects that are contained in graphics. The end goal is to communicate information clearly and efficiently to users via the information graphics selected, such as tables and charts. In his 1983 book “The Visual Display of Quantitative Information”, Professor Edward Tufte defines ‘graphical displays’ and principles for effective graphical display in the following passage: “Excellence in statistical graphics consists of complex ideas communicated with clarity, precision and efficiency. Graphical displays should: Continue reading this post>>
You don’t have to look at the expiration on your milk carton to know that it has soured – it usually gives you some pretty strong clues, like smell, discoloration, or a strange consistency. In the same way, you probably have an idea that your BI dashboard has gone bad – clutter and unreadable graphs are sure signs that it’s time for a refresh. Other clues are less obvious, like maybe your role has changed but your dashboard hasn’t changed along with it. Let’s dive into these clues and see if you can relate to any of them:
1. Your dashboard is too busy. The biggest limitation of dashboards is the physical size of your screen. When your dashboard was created, did it take this into account? Are all of your metrics on one screen, which forces you to do a whole lot of scrolling? A dashboard should not require the user to scroll left, right, up or down to see the entire screen. Try a creative way of accessing additional information, like implementing tabs or hierarchies to drill down into more detailed information.
2. Flashing lights and pretty pictures. Does your dashboard look like a fireworks display on the 4th of July? Certainly your dashboard needs to be attractive, but you can display a whole lot of nothing through the inappropriate use of graphs and graphics. Dashboards should be analytical tools, not just pretty pictures. They need to provide business value, which can be achieved through simple charts (read: not 3D) and appropriate animation, keeping the flash to a minimum. Here’s a tip: if you’re using stoplight indicators, think about making stoplight symbols a standard in your organization. That way, employees who are colorblind can still get value from your indicators.
3. Lack of a role-based view.
Decision-makers depend on insightful charts and graphs to help them make fast, accurate decisions. “Insightful” charts and graphs are easy to read and understand and are the right design for your data. The wrong chart type can throw everything off and make your dashboard unusable. For example, while pie charts are most often used to display the share or percentage of a total, they’re not good for comparing the relationship between two variables – a scatter chart is better for that. While bar charts are good for comparison, if you want to compare many categories of data over time, go with a line chart.
Are you tasked with creating the dashboards that are used every day at your organization? As dashboard experts, let’s take a look at a few practical examples of why certain charts are better suited to display certain types of data versus others. If you find this article useful, be sure to view our webinar recording Scorecard & Dashboard Development: A Detailed How-To, where you’ll get more practical tips to create interactive, “go-to” dashboards.
Sales data for the year may be best displayed on a bullet graph. This type of graph displays a fair amount of data in a small space, compares measures to enrich its meaning, and is generally a simple, uncluttered visual representation of data. With a bullet graph, the budgeted sales amount for the year is represented by the entire length of the bar; the actual value is represented by the thin bar in the forefront (blue on the sales bullet graph). The shaded grey areas (in our image) represent the values “poor,” “satisfactory,” and “good.” In our image, the sales data is satisfactory, approaching good. Stacking bullet graphs allows the user to compare values with ease – here, sales vs. costs. A bullet graph would even work well as a desktop widget since it can showcase an important KPI in a simple, space-efficient format.
Would a bar chart work for this same data?
A bullet chart is actually a variation of a bar chart. Even though bar charts are useful for comparing data as well, for our sales example, it may not be your best option. With a bar chart, you’d need to have 2 columns per month – one for actual and one for the target/budgeted amount. Alternatively, you could use a stacked bar chart, but that is basically what we have here with the bullet graph, only with even more data than a stacked bar chart typically offers. Because it would be difficult to track your progress over time, a standard bar chart isn’t the most efficient chart type for sales actual vs. budget data.
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