A literature review is a crucial step in determining the study topic. It provides necessary background information, a clear picture of what has been developed and investigated, and its relevance and gaps in existing research. As a result, the following subjects were reviewed: dashboards in general, their types and goals, and visualization approaches.
5.1.1 Review of Literature on Dashboards
There are four levels of information, according to Savoie (
2012): data, information, knowledge, and wisdom. Each level makes the previous one richer and more informative. The fist level is made up of facts with no meaning and is just input data. As stated by Few (
2006), collecting, processing, and storing data is well explored, but there is “little progress in using that information effectively.” As a result, to present data, it has to be turned into information, which is the second level of processing. To turn data into information, it must be organized and structured with a shared meaning. For example, we can organize the data into rows and columns, assigning titles and descriptions to them, and the data becomes meaningful as information. Furthermore, dashboards are the most effective approach to convey information (Savoie
2012).
EIS (Thierauf
1991), scorecards, and KPIs (Kaplan et al.
1997) have been studied since the 1990s. They are all used to support decision-making, measure performance, and monitor execution of activities, and according to Few (
2006) dashboards appear to be synonymous or simply a new name for them. However, nowadays, the definition of dashboards by Few (
2004) is the most used and common:
Visual display
of
the most Information needed to achieve one or more objectives
which
fits entirely on a single computer screen
so it can be
monitored at a glance.
It is evident from the definition that the dashboard’s visual appearance, as well as its objectives, is very significant. It should deliver appropriate and reliable content in a straightforward and understandable manner to the end-user. According to Few (
2006), most dashboards fail to communicate efficiently and effectively due to poorly designed implementation rather than a lack of technology.
Visualization of dashboards is essential not because of its beauty but because it can communicate with end-users with greater efficiency and richer meaning than plain text (Few
2006). As a result, visualization becomes more science than art because a successful dashboard is informed design, not just cute gauges, meters, and traffic lights (Few
2006).
Furthermore, while considering dashboard objectives, it is evident that different end-users would have varied objectives, requiring the development of different dashboards for each group of users. As a result, tailored dashboards are becoming increasingly useful (Few
2006; Johanssen et al.
2019), customized to meet individual needs to improve communication and suit the needs of users. In particular, faceted analytical displays give distinct views of the same data to different users for the purpose of analysis (Few et al.
2007); in other words, the same data is displayed in different ways.
5.1.2 Types of Dashboards
According to Eckerson (
2010), there are three types of dashboards: operational, tactical, and strategic. Each type, from operational to tactical, has more complex data, which means that for the first type, simple data is used, and for the strategic type, more complex data for purposes of analysis.
Each type differs in its objectives, functionality, and end-users, which is the reason for different data abstraction levels. But even if they have different usages, they overlap in some sense, which means that the same dashboard can be used for various purposes and by other end-users. For example, front-line workers can use both tactical and operation types of dashboards and managers can use all three of them. Thus, each dashboard type has its own features, but there is no clear boundary between them (Table
5.1).
Table 5.1
Dashboard types according to Eckerson (
2010)
Operational level is mainly used by front-line workers to track operational processes, such as those involving people, tasks, events, and activities, as they occur.
Furthermore, there are two subtypes of the operational level: detect-and-respond and incent-and-motivate. The first subtype relates to monitoring activities or optimizing processes. The second subtype is a dashboard to increase workers’ productivity by presenting the workers’ or team’s performance metrics.
Most operational level dashboards display metrics of low-level processes; they contain detailed data or sometimes are slightly summarized. Furthermore, the dashboards often offer only one level of data with no drill-down functionality and provide the most up-to-date information. The dashboards look like automobile dashboards with alerts, dials, and gauges.
Tactical level is used to optimize business processes and to analyze performance against goals. Dashboards emphasize analysis, and monitoring is also available. In most cases, the dashboard looks like an analytical or functional dashboard containing tables and charts describing what happened in the past. Also, it is worth mentioning that usually for tactical-level dashboards different users have different data presented depending on their role.
Interaction with charts and tables is a regular feature at the operational level. Drill-down, filters, sorting, changing views, pop-ups (Few
2006), and other features make it easier to interact with the dashboard and improve the user experience.
The dashboards used by mid-level managers and their appearance are somewhere between operational and strategic levels, allowing users to keep track of different processes and data in one spot.
Strategic level is mostly used by executives to review the progress toward strategic goals once a month or more rarely. In summary, the first two levels measure processes to understand what is happening now or in the short term, but the strategic level deals with long-term strategies.
Furthermore, some research includes a fourth type:
analytical. It contains a large amount of complex data and what-if scenarios to assist executives in their analysis and planning (Nadj et al.
2020).
In addition, dashboards can also be classified as static (read-only) and interactive. Despite that, Few (
2006) states that providing different varieties of data is meaningless, and nowadays static dashboards are not relevant anymore. Interactive dashboards can help to handle chunks of information effectively considering the growth of complexity and amount of data (Nadj et al.
2020).
5.1.4 Visualization Methods of Dashboards
In the study by Yigitbasioglu et al. (
2012), the authors underline the importance of interaction with a dashboard. Their research on dashboard graphical user interfaces distinguished two categories of design features: visual and functional.
Visual features refer to how data is displayed to the user; they influence how effectively and efficiently data is presented, and they directly affect the time for perceiving information. Inappropriate use of visual effects, such as varying surface styles, expanding the number and ranges of objects, overwhelming 3D objects, and non-value-adding frames, can make the understanding process more difficult. Gridlines inside charts, a high data-ink ratio, and the elimination of non-data-ink components in charts are all examples of improvements.
“Data-ink ratio is a parameter that defines the relationship of ink used to illustrate data to the overall ink leveraged to represent the chart” (Nadj et al.
2020).
An example of poor visual features is inappropriate use of color or data-ink ratio, which will distract or confuse users, for example, using yellow and red too often may attract attention and also may lead to the impossibility of highlighting errors or critical information (Nadj et al.
2020).
Green, yellow, and red should represent acceptable, satisfactory, and poor performance/alarms, respectively (Few
2006).
Functional features describe what the dashboard can do. Such features include pointing and clicking interactivity, which enables rolling down and up, filtering, sorting, brushing, illustrating more data, and additional information on pointing.
Such features are a step toward interactive dashboards, in which the user is actively participating in the data analysis process. However, the user’s effort to interact can lengthen the analysis process or have a negative impact on decision-making (Nadj et al.
2020).
An example of a poor functional feature is dashboards which fail to provide needed functionality to a user who cannot gain enough information (e.g., to analyze or plan) from dashboards due to a lack of these features.
Few (
2006) also includes standard practices in his study, such as visual and functional features:
Common features:
-
Using charts, tables, speedometer widgets for graphical representation
-
Dividing the full set of data to individual views
-
“Digital cockpit”—summary of performance by color-coded light indicator
-
Using gauges with traffic-light colors
In addition, in the study by López et al. (
2021), the authors provide different views and different kinds of charts to analyze the performance and distinguish different levels of abstraction to visualize the same data. According to the study, high-level strategic indicators are effective and improve decision-making processes.
-
Process performance strategic indicators (SI)—gauge chart showing the SI assessment value
-
Detailed SI—radar chart, quality factors (QF) for the SI assessment
-
Factors—radar chart, metrics for the QF assessment
-
Historical data view for metrics—line chart, metrics assessments