Sankey charts are a useful tool for data visualization that can help you understand complex flows and relationships. They are named after the Scottish engineer and physicist, Captain Robert H. Sankey, who developed them in the late 19th century to illustrate water flows through a factory. Since then, Sankey charts have been used in various fields, such as energy, ecology, economics, and epidemiology, to name a few.
In this article, we will discuss the creation and applications of Sankey charts, highlighting their power and versatility in data visualization.
Creating Sankey Charts
Data Preparation
Creating a Sankey chart starts with preparing your data. You need to organize your data in a specific format, typically with three main columns:
- Source: The starting point of the flow.
- Sink: The endpoint of the flow.
- Value: The total transfer amount or the ratio of the flow segment compared to the total transfer.
You might also have labels for better readability, colors to differentiate categories, and total flow values.
Choosing the Right Tool
Several tools and software options are available for creating Sankey diagrams, catering to both beginners and experienced users. Here are some popular ones:
- Tableau: A powerful data visualization software where you can drag and drop columns to create Sankey charts. It supports various data sources from spreadsheets to databases.
- D3.js: A JavaScript library that allows for customizations and deep control over the chart. It is more suitable for developers and those looking for more customization capabilities.
- Sankey.js: A lightweight JavaScript library specifically for creating Sankey diagrams. It provides an easy-to-use API and is great for embedding charts in web pages.
- Gephi: An open-source network analysis and visualization software that includes Sankey diagrams as part of its features. It’s particularly useful for larger datasets and complex networks.
Design and Customization
Once your data is prepared and the tool is chosen, it’s time to design your chart:
- Positioning and Sizing: Adjust the layout of the chart to fit your space or screen. This includes the width, height, and the orientation (horizontal or vertical).
- Colors and Legends: Use colors to represent different categories while setting up a legend. This helps in enhancing readability and making the chart more informative.
- Labels: Incorporate meaningful labels for the source, sink, and any category nodes to provide context.
- Effects and Interactivity: Sankey charts in modern tools often have options for hover effects, animations, and even interactivity, which can greatly enhance user engagement and understanding.
Applications and Benefits
Sankey charts are incredibly versatile and can be applied in several scenarios, such as:
- Energy Flows: Mapping energy consumption, production, and distribution across different sectors and regions.
- Supply Chains: Visualizing the flow of goods, materials, or services across different stages and suppliers.
- Economic Flows: Demonstrating monetary transactions, financial flows, and wealth distribution.
- Resource Allocation: Showing how resources are allocated across departments or organizations.
- Epidemiology: Tracing the spread of diseases through populations or regions.
- Network Analysis: Mapping relationships within complex networks like social media interactions, or web page linkages.
Conclusion
Sankey charts are a powerful tool for data visualization, enabling you to see and understand complex flows and relationships more easily. They are suitable for a wide range of applications, from explaining intricate processes to gaining insights from large datasets. By leveraging modern data visualization tools, you can create compelling and informative Sankey charts that communicate your data stories effectively and make your analysis more accessible to your audience.
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.
