UX & Design
12
 minute read

The Art of Data: UX, Gestalt Laws, and Colour Theory in Data Analytics and Visualisation

Bogdan Donose
29 Jun
2024

Data analytics and visualisation have become essential tools in our data-driven world. They transform raw numbers into comprehensible insights, guiding decisions in business, healthcare, education, and more. But what differentiates a simple chart from a compelling data story? The secret lies in the meticulous application of user experience (UX) principles, Gestalt laws, and colour theory. In this blog post, we’ll explore these elements and uncover how they contribute to creating effective and engaging data visualisations.

Understanding UX in Data Visualisation

User Experience (UX) design in data visualisation focuses on making data easily accessible, understandable, and actionable for users. It’s not just about making things look pretty—although aesthetics are important—but about creating intuitive and meaningful experiences.

When users engage with a data visualisation, they should be able to extract the information they need quickly and without confusion. This involves several key principles:

  • Clarity: Ensuring that the visualisation is clear and legible.
  • Consistency: Maintaining uniformity in design elements.
  • Efficiency: Allowing users to accomplish their goals with minimal effort.
  • Engagement: Making the visualisation interesting and engaging.

A well-designed data visualisation should be a seamless blend of these principles, guiding users to insights effortlessly.

UX in data visualisation
© Springboard - UX

The Magic of Gestalt Laws

The Gestalt principles, originating from psychology, describe how humans perceive visual elements as unified wholes rather than just a collection of individual parts. These principles are critical in UX and design, particularly in data visualisation, because they help us understand how users will interpret visual information. Let’s dive into the most relevant Gestalt laws for data visualisation.

1. Law of Proximity

The law of proximity states that objects close to each other are perceived as a group. This principle is crucial when designing data visualisations, as it helps to organise information and reduce cognitive load.

Example: In a scatter plot, data points that are close together are perceived as a cluster, indicating a relationship or pattern.

Proximity law in action.
Application Tip: Use spacing strategically to group related data points and separate unrelated ones. This can help users quickly identify trends and outliers.

2. Law of Similarity

The law of similarity suggests that elements that look similar are perceived as part of the same group. This can be achieved through consistent use of shapes, colours, or sizes.

Example: In a bar chart, bars of the same colour and style are seen as belonging to the same category.

The use of shapes, colours or sizes exemplify how groupings can be perceived.
Application Tip: Use consistent design elements to group similar data points. For instance, use the same colour for bars representing the same category across different charts.

3. Law of Continuity

The law of continuity indicates that the human eye prefers continuous figures. In data visualisation, this means users are likely to follow lines and curves, perceiving them as continuous flows of data.

Example: In a line graph, the continuity of the line helps users follow the trend over time.

Our perception tends to see objects arranged in lines or curves as more related or grouped

Application Tip: Ensure that lines and curves in your visualisations are smooth and continuous to guide users through the data seamlessly.

4. Law of Closure

The law of closure posits that people tend to perceive incomplete shapes as complete. This principle can be useful for creating more engaging and intuitive visualisations.

Example: In an infographic, using partial shapes or lines can suggest completeness without overcrowding the visual space.

(Left) Small circles or one big one? (Middle) Green shapes or a panda bear? (Right) Three curves or one full circle?

Application Tip: Leverage partial shapes or suggestive lines to imply completeness and encourage users to engage more actively with the visualisation.

5. Law of Figure/Ground

This principle describes how we separate objects (figures) from their background (ground). Effective use of figure and ground helps highlight key data points and information.

Example: Highlighting a specific bar in a bar chart against a muted background draws attention to that particular data point.

Principle of figure-ground segregation exemplified with shapes.

Application Tip: Use contrasting colours and shades to distinguish important data from the background, ensuring that key information stands out.

The Power of Colour Theory

Colour is a powerful tool in data visualisation, influencing both aesthetics and usability. Understanding colour theory can help designers create visualisations that are not only attractive but also effective in communicating information.

1. Choosing the Right Colour Palette

A well-chosen colour palette can enhance the readability and appeal of a data visualisation. Here are some tips for selecting the right colours:

  • Analogous Colours: These are colours that are next to each other on the colour wheel. They create a harmonious and cohesive look.
  • Complementary Colours: Colours opposite each other on the colour wheel. They provide high contrast and can highlight differences effectively.
  • Monochromatic Colours: Variations in lightness and saturation of a single colour. They offer a subtle and professional look.

Example: Using a blue monochromatic palette for a line graph can convey a professional tone and ensure readability.

2. Colour and Emotion

Colours evoke emotions and can influence how data is perceived. For instance:

  • Red: Can indicate urgency or importance, but also danger or error.
  • Green: Often associated with growth, success, and positive values.
  • Blue: Conveys trust, calmness, and professionalism.

Application Tip: Choose colours that align with the message you want to convey. For instance, use red to highlight critical data points that need immediate attention.

3. Accessibility and Inclusivity

Consider colour vision deficiencies (CVD) when designing your data visualisations. About 8% of men and 0.5% of women have some form of colour blindness, so it’s important to ensure your visualisations are accessible to everyone.

Application Tip: Use colour-blind friendly palettes and always combine colour with other visual cues like shapes or patterns to convey information.

Putting It All Together

To illustrate the application of these principles, let’s walk through the creation of a simple data visualisation step-by-step.

Step 1: Define the Objective

Start with a clear objective. Suppose we want to visualise sales data over the past year to identify trends and peaks.

Step 2: Choose the Right Chart Type

For time-based data, a line graph is often the most effective choice. It leverages the law of continuity to help users follow trends over time.

Step 3: Apply Gestalt Principles

  • Proximity: Group data points by month to show monthly trends.
  • Similarity: Use the same colour for all data points to indicate they belong to the same category.
  • Continuity: Ensure the line is smooth and continuous.
  • Closure: If we show sales goals as dashed lines, users will mentally complete the trend.
  • Figure/Ground: Highlight the peak sales month with a brighter colour.

Step 4: Select a Colour Palette

Choose a colour palette that aligns with your brand and the message you want to convey. For a professional and trustworthy look, a blue monochromatic palette might be ideal.

Step 5: Ensure Accessibility

Use a colour-blind friendly palette and add data labels or markers to ensure that the visualisation is readable by everyone.

Step 6: Add Interactive Elements

For digital visualisations, consider adding interactive elements like tooltips, and filters to enhance user engagement and make the data exploration more dynamic.

Final Visualisation

Your final visualisation should be a harmonious blend of UX principles, Gestalt laws, and colour theory. It should tell a clear, engaging story and guide users to meaningful insights effortlessly.

Conclusion

Creating compelling data visualisations is an art that combines science, psychology, and design. By understanding and applying UX principles, Gestalt laws, and colour theory, you can transform raw data into powerful visual stories that engage, inform, and inspire your audience. Remember, the goal is not just to display data, but to communicate it effectively, making complex information accessible and actionable. So, go ahead and create visualisations that not only inform but also delight your users—because in the world of data, a picture truly is worth a thousand words.

Happy visualising!