3 UX Design Principles for Better Data Visualization
By: Destin Gong
Tags: Data, Data Analysis, UX, Design, Dashboard

Three UX Design Principles

1. Just KISS

I am sorry it is not what you are thinking ;)

KISS means “keep it simple, stupid”. Good user experience doesn’t mean stacking all the beautiful graphics together. It looks amazing, but your attention is dispersed everywhere on the screen, and to be honest, it is tiring. It is also not about creating complicated graphs that show off how scientific and professional they look, that only scare people off.

There are some graphs we’d better avoid using based on this principle. For example, only use 3D chart if it is really necessary. Most of the time, the third dimension just doesn’t serve any purpose. Instead, it makes the visuals so heavy and thick to digest.

Another example is secondary y-axis, it takes more frictions and efforts to understand which axis the chart is mapped against. Like this chart below, can you easily tell which axis is for the bar chart and which one is for the line chart within 3 seconds?

Therefore, keep it minimal and eliminate clutter, these simple tricks can additionally make your dashboard looks cleaner instantly:

1. Use no more than five colours (or 3 main colours) in one dashboard.

2. Un-bold chart captions and titles. Make them concise.

3. Remove chart gridlines and borders.

Delivering knowledge is not about showing off how skilled you are, rather it is to highlight common understanding between deliverers and receivers. Just KISS!

2. Form Follows Function

Built upon the previous point, it is essential to design the dashboard that actually delivers the message to the receivers, hence it is required to meet the key objectives. That is, to prioritize what are the core functions and insights the dashboard needs to demonstrate. Then choose the forms correspondingly. Emphasize on selecting the most appropriate chart that is aligned with the data type.

Bar chart compares the measures of categorical data.

Histogram looks very similar to the bar chart because it also consists of bars. However, instead of comparing the categorical data, it breaks down a numeric data into interval groups and shows the frequency of data fall into each group.

Line chart indicates trend and development of variables over time, usually represented by one numeric data against a date-type variable. It is commonly used in time series analysis.

Pie chart is used to represent the percentage and weight of categorical data. Intuitively depict proportions of a whole.

Map shows numeric data that can be grouped by regions. Using gradient colors is a great way to visualize the density difference in various geographical locations.

Scatter plot visualizes the correlation between two numeric variables. Common to identify relationships such as linear regression, logistic regression etc.

These are the most basic charts. There are more complicated graphs that perform advanced analytics such as heatmap, treemap, box plot etc … That’s another story that is definitely worth diving deeper. However, it is not the main focus of this article.

Most importanly, it is to always keep the users in mind and be clear about the objectives. It doesn’t matter how fancy the form is if it doesn’t bring any functions.

3. Take the Advantage of Hierarchy

Hierarchy is essential in terms of indicating viewers where to look first. It can be constructed implicitly using size, color, position etc.

Size: Large and bold fonts are more likely to stand out whereas small and thin texts are less prioritised. If we are using texts to display statistics, make sure they do pop up from other text forms such as title and caption. This principle goes beyond just text, using different sizes of shape also creates a hierarchical layout.

Position: Human visual perception determines that we are more likely to look at the top left corner or the center of the screen. Therefore, the most important information should be located at these areas where viewers distribute most of their attention.

Color: Bright colors are more likely to stand out whereas pale colors will be brought to the background. Another general rule is that color that breaks the consistency will be perceived as the important message. Therefore, make use of contrast to make the key information grab your audience’s attention.