Why visualization?

In Figure 1, on the left is the mapped flow of people between towns in Singapore, while the right shows the key flow structure---the information---that was analyzed from the data in the left.

From Data to Information, then Insights¶

• Data: Raw facts, figures, or observations collected and recorded] in various forms, such as text, numbers, or images. Data is the basic building block for understanding and analyzing phenomena or trends.

• Information: Organized, structured, and processed data that provides context and meaning, making it useful and relevant to specific users or situations. Information helps answer questions and guide decision-making.

• Insights: Deep, meaningful conclusions and understanding derived from analyzing and interpreting information. Insights uncover patterns, trends, or cause-and-effect relationships, enabling informed decisions and new perspectives.

Geovisualisation is a series of explorations and analyses, that includes using various techniques and methods, e.g., thematic mapping, exploratory spatial data analysis, to uncover the underlying patterns, to get better understanding of geographical phenomena.

The Key Steps of Data Visualisation: OTAS¶

• Observe

• Think

• Assess

• Show

Observe¶

• What can be SEEN?

• Ensure you understand the metadata.

• Look into the data.

• Get your hand dirty: Create relevant plots or maps using the data.

  • whatever plots/maps that you can think of, sky is the limit

• Look at those plots and maps...

• Divergent thinking, brainstorming

Think¶

• What are the CAUSES?

• How does it look?

• Are there any familiar or expected patterns? (that you may have seen somewhere before)

• Is there anything looks unusual and strange? (something that really stands out)

  • Is there anything wrong?

• Are there any unexpected patterns? (something beyond your expectation)

  • unexpected patterns are usually the interesting one, if they are real

  • counter-intuitive

• What could be the possible reasons behind these patterns?

• Expanding and synthesizing from the brainstorming step

Assess¶

• How to VERIFY them?

• Review and (re)evaluate your initial ideas or thoughts, even if they seem immature, unconventional, or funny.

• Test your hypotheses or thoughts to ensure their validity.

• Double-check for any possible (stupid) mistakes made during

  • data processing,

  • calculation,

  • unit transformation,

  • map projection, or

  • visualization.

• Literature review for confirmation/contrasting the findings.

• Convergent thinking, rigourously evaluating every idea

Show¶

• How to VISUALISE them?

• (Re)Drawing the plots & maps

• Think about the layouts

  • potrait, landscape

  • combining multiple subplots

  • sequences

  • colours

  • text font family, size, and positions

• Show it to people

• Communicate based on it

• Getting feedbacks

OTAS Flow¶

Summary¶

• There is no strict rules for doing data visualisation

• The four OTAS steps are just a quick guideline for the “visual thinking process”

  • Observe: divergent thinking & brainstorming

  • Think: extending & synthesing

  • Assess: convergent thinking & double checking

  • Show: presentation

• Some people skip the Think and Assess steps and jump from drawing initial plots/maps step to the last showing/communicating step.

  • Their results could be bias, not comprehensively capture the thoughts