Mastering Sankey Charts: A Comprehensive Guide to Visualizing Material and Data Flows
Sankey charts are a type of flow diagram in which the width of the arrows is proportional to the flow quantity, thus providing an attractive, visually intuitive way to demonstrate complex material and data flows. This guide aims to help you understand, create, and interpret Sankey charts effectively without any prior knowledge.
Understanding Sankey Charts
Sankey diagrams originated in the early 19th century, with a Scottish engineer named Matthew Henry Phineas Riall Sankey. Sankey charts are now widely used in energy, logistics, economy, and many other fields to illustrate how materials or data flow between different points or nodes.
Components and Characteristics
To create meaningful Sankey charts, it’s crucial to understand their components and characteristics:
– Nodes represent the points where flows are initiated or received.
– The edges, connecting the nodes, depict the flow paths and quantities. The width of the edges indicates the volume of flow.
– Arcs and arrows often denote direction in the flow diagrams.
– Labels are used to identify specific nodes or data regarding the quantity of flow.
Designing Sankey Charts
Designing a Sankey chart involves selecting data, determining the scale, and crafting the visual elements:
1. Data Selection:
Start with the dataset that includes the source (origin), destination (sink), and the amount of material or data flowing between these nodes.
2. Scale:
Choose appropriate scales for both magnitude and directions based on the data range to ensure clarity and readability.
3. Visualization Elements:
Style your chart with colors, labels, and annotations. This will not only make the data more digestible but also enhance the presentation of your charts.
Tips & Tricks
Effective creation and utilization of Sankey charts heavily rely on the following strategies:
– Always arrange nodes in a logical manner, typically with the most sources on the left and destination nodes on the right, or by grouping related flows together.
– Opt for color differentiation by flow instead of by source or destination for complex charts. This allows viewers to quickly identify patterns, especially when dealing with multi-input and multi-output flows.
– Use annotations to supplement information that cannot be clearly discerned from the width of the arrows.
– Maintain the legend, ensuring proper visibility and relevance in the context of the chart.
– Lastly, utilize interactive elements in digital Sankey diagrams for a more engaging and user-friendly experience.
Conclusion
Mastering Sankey charts is about leveraging their unique ability to represent complex data flows efficiently and visually. By understanding the fundamentals, choosing data wisely, and applying the right design principles, you can create informative and visually appealing Sankey diagrams to communicate your message effectively to your audience.
Remember that while charts convey the value and volume of quantities, they also encourage a dynamic and thoughtful exploration of relationships and patterns within the data flow. With these principles in mind, you are on your way to becoming a skilled Sankey chart maker.
