Sankey diagrams, named after Henry Sankey, an engineer at London’s Woolwich Arsenal, who introduced them in the early 1910s, are a powerful visual tool that has found widespread application in a variety of fields, including energy flow analysis, data analytics, and environmental studies. These charts are particularly effective in displaying the direction and magnitude of large quantities of data. In the realm of visual storytelling, sankey diagrams offer a unique way to depict relationships between different variables, making complex data sets more accessible and understandable to the average viewer.
Understanding Sankey Charts
Sankey diagrams are designed to visualize the flow process by tracing the movement of values from one node to another. They are built using colored lines (often referred to as “arrows”) of varying widths that represent the quantities of matter or energy flowing between different points. The thickness of these lines directly corresponds to the magnitude of the flow, making it easy for the viewer to quickly grasp comparative values among different paths.
Creating a Sankey Chart
Creating a sankey chart can be done using a variety of software tools, which include proprietary programs like Tableau, and freeware options like Python libraries (e.g., matplotlib, Plotly) and interactive platforms such as the excellent open-source platform Observable. The process generally involves several steps:
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Data Preparation: Gathering and compiling the data points that you wish to include in your sankey chart is the first step. It’s crucial to ensure that your data is clean and correctly formatted to facilitate accurate visualization.
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Defining Sources and Sinks: Identify the inputs (sources) and outputs (sinks) of your sankey diagram. Deciding on the starting and ending points of your flow is critical for structuring your data correctly before visualization.
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Organizing Points: Once you’ve defined your sources and sinks, organize the points between them. This involves determining the intermediary nodes through which the flow might pass (if applicable).
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Data Visualization: Using the software of your choice, enter your data followed by configuring the software to plot the sankey diagram. You’ll need to specify the source, sink, and intermediary nodes, as well as the value of the flow for each connection.
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Finalizing: After the program generates your chart, some manual adjustments might be necessary to optimize the flow and readability of the diagram. Making informed edits can greatly enhance the clarity and impact of your visualization.
Applications of Sankey Diagrams in Visual Storytelling
Sankey diagrams are incredibly versatile tools for visual storytelling. They can help explain complex concepts such as the composition of energy flows, the breakdown of an audience within social media platforms, or the distribution of resources within an organization, among many others. By illustrating the transformation or movement of data among various categories, sankey diagrams can significantly enhance our understanding and engagement with large and sometimes intricate data sets.
Illustrating Resource Allocation
In the context of financial reporting or project management, sankey diagrams are invaluable for visualizing where money or resources are being allocated and how they are being used. This can help stakeholders in making informed decisions based on a more transparent and visual representation of their financial health or project progress.
Exploring Data Flow within Businesses
Sankey diagrams can also be used to examine and improve the efficiency of information or data flows within organizations. By illustrating the direction and volume of data movement among different departments or systems, managers can identify bottlenecks and inefficiencies, leading to better strategic planning and operational improvements.
Communicating Energy and Resources
Sankey diagrams are particularly useful in the analysis of energy and materials cycles, allowing users to understand the flow and transformation of materials and energy across systems. This is evident in environmental and sustainability reports, where sankey diagrams often serve as a pivotal tool in illustrating the impact of processes on the environment.
Conclusion
Sankey diagrams are a powerful tool in the arsenal of visual storytelling. Their ability to depict the flow of data in a clear and concise manner makes them a valuable asset in a variety of fields, particularly those with complex datasets. By leveraging sankey diagrams, professionals and storytellers alike can communicate ideas more effectively and lead to better informed decisions and actions. As data visualization and storytelling continue to evolve, sankey diagrams will likely remain a cornerstone in the visual communication of complex data flow.
SankeyMaster
SankeyMaster is your go-to tool for creating complex Sankey charts . Easily enter data and create Sankey charts that accurately reveal intricate data relationships.
