Decoding Complexity with Sankey Diagrams: A Practical Guide to Visualizing Flows and Interconnections
Sankey diagrams represent complex systems using arrows that display flows of data, energy, or materials across an interconnected series of entities. They’re an indispensable tool for illuminating convoluted networks and helping stakeholders and decision makers understand the underlying dynamics of a system. In this guide, we will delve into how to effectively utilize Sankey diagrams for decoding complexity.
### What Are Sankey Diagrams?
Sankey diagrams belong to the category of flow diagrams, visualizing the movement from one part of a system to another. Named after Captain Hugh Sankey, who used this method in the late 1800s to depict energy consumption in a factory, Sankey diagrams represent how items move across nodes (or vertices) within a system—enabling one to easily see the flow paths and magnitude of throughput.
### Key Characteristics of Sankey Diagrams
#### 1. **Flow and Width**
– Each arrow or ‘link’ in a Sankey diagram’s branches is proportionate to the flow volume it represents, making it immediately clear which paths carry more or less traffic.
#### 2. **Arrows and Nodes**
– Nodes symbolize the entities within a system, while arrows represent the connections between these entities, showing the direction and flow of material or data.
#### 3. **Color Coding**
– Different line colors can be used for various data sets or categories to facilitate easy differentiation between them.
#### 4. **Hierarchy and Nesting**
– Sankey diagrams can nest nodes within larger entities, visually showing sub-system relationships, which is particularly useful for hierarchical systems.
### Practical Guide to Using Sankey Diagrams
#### Step 1: Define the Entities and Their Relationship
– Identify and classify the elements within your system. For a data analytics team, these might be datasets or user segments. For a retail supply chain, entities might include suppliers, factories, warehouses, and retail outlets.
#### Step 2: Quantify the Flows
– Determine the volume or intensity of flows between these entities. For data flow, this could be the size and frequency of transactions between platforms. For a supply chain, it might be units of product moving through each node.
#### Step 3: Choose Your Visualization Software
– Select a visualization tool that supports Sankey diagrams. Popular software includes Tableau, Microsoft Power BI, and dedicated tools like Gephi. Ensure the software you choose offers the flexibility to customize link direction, width, and color.
#### Step 4: Design Your Sankey Diagram
– Start designing your diagram by mapping out nodes and the appropriate links. Assign link widths based on the flows’ intensity and choose distinct colors to represent different types of data sets or phases in a process.
#### Step 5: Analyze and Enhance the Diagram
– Evaluate the visual representation of the flows within your system. Enhance readability and clarity by adding labels, categorizing flows, and adding notes that explain complex relationships. If necessary, simplify or adjust the diagram to ensure it’s understandable and useful for the intended audience.
#### Step 6: Continuous Improvement
– As you gain more insights from the Sankey diagram, update your entity definitions, flow data, and visualization to reflect changes and maintain accuracy. Regular updates can help in refining understanding and decision-making around system operation.
### Conclusion
Decoding complex systems through the use of Sankey diagrams reveals hidden insights, optimizing decision making, and improving communication with stakeholders. By carefully mapping entities, analyzing flows, and customizing visualizations, these diagrams become powerful tools for making sense of intricate datasets, supply chains, and other interconnected systems. Whether designing a complex system, analyzing data flows, or planning a business strategy, Sankey diagrams provide a visual lens through which to comprehend and manage complexity effectively.
