What makes a good viz?

What makes a good viz? - Part 2

25th August 2017 | Chris O'Mahony

Size and colour used to represent the same measure

Question complexity

Every addition in complexity to a visualisation should add value. For every extra dimension or measure that is added to a visualisation, the user will require more time and thought to process the information that is being presented to them. If that added complexity does not add value to the message of the visualisation or dashboard, this is essentially wasted time. As a general rule of thumb, do not do one thing in two different ways on the same single visualisation. For example, a bar chart showing Students by academic achievement, does not need the bars coloured by academic achievement as this doesn’t add any additional value.

These two users will probably want to see different levels of detail.

Consider your user

Consumers for published dashboards and reports can vary dramatically. Some users will be happy to delve into the details of issues and have the time and inclination to do so, whereas others will just require figures represented at a high level and immediately digestible.

Use sequential colours rather than a random colour palette.

Consistency

When creating a dashboard, ensure that consistency is applied, particular in relation to colours. If a colour palette is used somewhere within your dashboards to represent something, it should be used elsewhere to represent same element. If this cannot be followed, ensure that legends are placed in appropriate positions, so that the colour identification is clear.

Colour Sequencing

If using colours across a sequence, such as a number of years, use sequential colours rather than a random colour palette. This should make it easier for the user to intuitively interpret the data and the dimensions it describes.

Gutenberg diagram, an age-old concept developed by Edmund C. Arnold.

Signpost functionality

It is very easy when you are creating a dashboard to know how everything interacts and what behaviour is to be expected. However, for a new user approaching a dashboard cold, this can often be a tricky process. It is best to offer some kind of guidance on the dashboard to functionality or features that they may not be expecting.

Read top-left to bottom-right

Conventionally, our culture automatically reads from the top-left to bottom-right. We can take advantage of this trait in dashboard design by putting the key, high level information at the top-left of the dashboard (for example KPI boxes). As the eye travels to the bottom-right, it is a natural place to put the visualisations that are at the lowest level of granularity (such as a scatter plot).

Thanks for reading! Any questions, please get in touch at vizi.education.

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