Unleashing the Power of Flow: A Comprehensive Guide to Creating and Interpreting Sankey Charts
Sankey charts are information visualizations that vividly show how quantities (such as mass, energy, or money) move from source to target. Commonly confused with flow charts, these unique diagrams provide a complete picture of the “traffic” of the value stream, revealing the intricate interrelationships and distribution patterns that are typically hard to grasp with static charts. This comprehensive guide aims to unlock the power of Sankey charts by detailing their creation and interpretation processes.
### Creation of Sankey Charts
Understanding how to create a Sankey chart begins by defining the problem area and data collection. You’ll need the following components:
#### 1. Start by Identifying the Components
The most fundamental step involves identifying the components of the process you want to display – the sources, targets, and quantities (such as volume or amount).
#### 2. Calculate the Quantities and Flows
Once the major components are identified, calculate the flow or quantity moved between each pair of components. This should include data about sources, sinks, and all intermediate flows.
#### 3. Prepare the Data
Organize the data in a format specific to Sankey charts, where columns represent the components, rows represent the pairs of components, and values indicate the flow or quantity.
#### 4. Choose Your Tool
Select a tool that suits your skill level. Options range from software like Microsoft Excel and Google Sheets to comprehensive tools such as Tableau, Python libraries like Plotly and Matplotlib, and R with ggplot2 or Tidyverse.
#### 5. Create the Chart
Within the selected tool, create the Sankey diagram. This typically involves dragging and dropping components, specifying the data mapping, controlling the positioning, and adjusting aesthetics like colors to represent different flows or quantities.
#### 6. Refine the Chart
Make any necessary adjustments to ensure clarity and readability. This might include:
– Adjusting the link widths to visually represent the flow magnitude.
– Adding labels for clarity.
– Highlighting certain flows or comparing flows in some way.
#### 7. Finalize and Save
Review the chart for accuracy and effectiveness. Once everything is as desired, save your work for future reference or sharing.
### Interpreting Sankey Charts
Interpreting Sankey charts involves several key considerations:
#### 1. Determine the Starting Point
Identify the source, typically the beginning of the pipeline or the largest input, and work your way through the diagram, observing how the flow progresses and changes.
#### 2. Analyze the Flow Paths
Carefully analyze the routes flows take between different nodes. This can reveal where the maximum or minimum amount of flow is concentrated or distributed unevenly.
#### 3. Observe Changes in Width
The width of the Sankey links directly correlates with the flow quantity, with wider lines indicating substantial flow volumes.
#### 4. Identify End Points and Feedback Loops
Look for sinks (end points where flows terminate) and check for any feedback loops, which signify cyclic or repetitive flows within the system.
#### 5. Compare Different Flows
If the chart includes multiple series or layers, compare the quantities and trends across different flows to understand which routes are the most efficient or influential.
#### 6. Look for Patterns and Trends
Sankey charts can reveal patterns, such as bottlenecks or flow dominance. Identify these features to optimize processes or allocate resources more effectively.
#### 7. Contextualize with Additional Data
Incorporate contextual information, such as economic indicators or geographic data, to enrich your interpretation and provide deeper insights into the interconnectedness of the elements depicted.
### Conclusion
By mastering both the creation and interpretation of Sankey charts, you can effectively communicate dynamic flow complexities across various fields. This intricate and descriptive visualization can help leaders, researchers, and data analysts across businesses, industries, and organizations to make informed decisions based on the profound insights these diagrams provide. Whether you’re modeling traffic patterns, financial transactions, or biological flows, Sankey charts offer a powerful way to explore and understand the intricate movements and connections within systems, enhancing knowledge and facilitating efficient problem-solving strategies.
