When it comes to visualizing flows of data, one chart stands out from the rest: the Sankey chart. This type of chart is designed to show the movement and distribution of a continuous quantity, making it an invaluable tool for industries that need to understand the flows of resources, materials, or information. In this article, we’ll dive into the creation and application of Sankey charts, understanding how they can unlock insights in a streamlined fashion.
What is a Sankey Chart?
A Sankey chart is a specialized flow chart that demonstrates the movement of a quantity through various stages or entities. It’s named after Captain Matthew Henry Phineas Riall Sankey, who used this type of diagram in the 1890s to show the energy losses in a steam engine. The chart uses horizontal bands, known as flows, whose widths represent the magnitude of the flow. These bands start and end at nodes, which are typically rectangles and circles. Each flow connects the nodes, symbolizing the movement of a quantity.
How to Create a Sankey Chart
Creating a Sankey chart involves several steps:
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Data Preparation: Gather the necessary data, typically in a format that includes the source, destination, and the volume of flow between them. This might be in the form of a CSV file with columns for source, target, and value.
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Choose the Right Tool: While you could create a Sankey chart manually using applications like Microsoft Excel, for more complex and precise designs, specialized software or libraries in programming languages like Python (with libraries like SankeyPlot, PySankey) or JavaScript (with libraries like D3.js) are preferable.
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Design the Layout: Define how flows connect nodes and how the width of the bands reflects the magnitude of the flow. This often involves specifying colors, node positions, and the width of the links.
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Visualization: Use the chosen tool to implement the design, with interactive features (like tooltips, zooming, and filtering) added for user convenience and analysis.
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Customize and Optimize: Adjust visual elements like colors, labels, and spacing to ensure clarity and ease of use. Keep the chart simple and uncluttered to facilitate better data comprehension.
Applications of Sankey Charts
Sankey charts find extensive use across various fields:
- Environmental Science: To illustrate the flow of energy or materials through ecosystems or energy systems.
- Economics: For showing the movement of goods, services, or investments between countries or industries.
- Sustainability: To track the flow of resources from production to consumption to waste, aiding in efficiency and recycling strategies.
- Supply Chain Management: To map the flow of products from raw materials to end consumer, highlighting efficiency and identifying potential bottlenecks.
- Healthcare: For tracking the flow of patients through healthcare systems, resources, or treatment pathways.
- Social Sciences: To depict the flow of money, influence, or information in networks.
Best Practices and Tips
- Simplicity is Key: Do not overly complicate your Sankey chart. Use it to convey clear information about the flow without overwhelming the viewer.
- Legibility: Ensure that all labels, node names, and flow values are readable, especially in larger charts.
- Consistent Use of Colors: Use distinct, yet harmonious colors for different flows to enhance visual differentiation and readability.
- Interactive Elements: If possible, add interactive features that enable users to engage more deeply with the data, such as filters or the ability to focus on specific parts of the chart.
By following these guidelines, you can create effective and insightful Sankey charts that serve as powerful tools for data analysis and communication.
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.
