B.3 Data and information visualisation Flashcards
Identify effective visualisation methods for knowledge discovery and the representation of information.
What is data visualisation?
The creation and study of the visual representation of data.
What is the main aim of visualisation in health informatics?
To assist with the discovery of patterns or to communicate data, information, and/or knowledge clearly and effectively.
True or False: Visualisation can easily be done incorrectly.
True
What is crucial for effective visualisation?
User perception and enhancing their understanding.
According to Few, what must be followed to visualise data effectively?
Design principles derived from an understanding of human perception.
List five questions to assess data visualisation effectiveness according to the Interaction Design Foundation.
- Indicate how data values relate to one another?
- Represent the quantities involved accurately?
- Make it easy to compare these quantities?
- Make it easy to see a ranked order of values?
- Make obvious how the information should be used?
What percentage of deaths in Australia were accounted for by the 20 leading causes in 2011?
Around two-thirds.
Fill in the blank: A pie chart provides a sense that the data represents the _______.
[proportions of a whole]
What is a major disadvantage of pie charts?
Requires continual crossover between the chart and a legend.
What is a pro of vertical bar charts?
More easily read in terms of relative values.
What is a con of horizontal bar charts?
Dominated by unusable data.
What is the purpose of modified horizontal bar charts?
To focus attention on the most important causes and represent proportions clearly.
Who are the two groups of actors involved in data visualisation?
- Designers of visualisations
- Consumers of visualisations
What are the objects involved in data visualisation?
The concepts, data, information, and knowledge being visualised.
What should be defined when creating a data visualisation?
The goals and objectives of the specific visualisation.
What consideration must be made regarding consumers of visualisation?
Different categories of consumers may perceive information differently.
List three key considerations when understanding the object of visualisation.
- Is it encodable?
- What are the important dimensions?
- What will be the role of position?
What are some tools of visual representation?
- Position
- Length
- Angle
- Slope
- Area
- Volume
- Density
- Colour saturation
- Texture
- Connection
- Containment
- Shape
- Similarity
- Proximity
What does Gestalt Theory suggest about perception?
The brain can understand parts through the lens of the whole.
List the constructs of Gestalt Theory.
- Proximity
- Similarity
- Closing
- Simplicity
- Continuity
- Figure/background
Fill in the blank: Vertical predominance indicates that a vertical line can look _______ than a horizontal line.
[longer]
What is a key concept in human visual perception?
Shape and space perception.
What is an example of how overlapping affects perception?
An object partially overlapped by another is perceived as more distant.
What does the HSL model examine?
Colour in three different dimensions.
What happens to an object that is partially overlapped by another?
It is perceived as more distant.
How does size influence perception between two objects?
The biggest object seems closer.
What does relative clarity imply in perception?
The clearest object seems nearer.
What is linear perspective in terms of object size perception?
Objects of the same size can appear of different sizes, and vice versa.
What are the three dimensions examined by the HSL model of colour?
- Hue
- Saturation
- Luminance
What does hue refer to in the context of colour?
What most people think of as colour – reds, blues, yellows, etc.
What does saturation refer to in colour?
Intensity of colour; high saturation means less grey and brighter appearance.
What does luminance represent in colour?
How much white or black features in a colour; higher luminance means brighter colour.
What is the maximum and minimum saturation in terms of grey?
Zero saturation is maximum grey; maximum saturation has no grey.
What is the maximum and minimum luminance in terms of black and white?
Zero luminance is black; maximum luminance is white.
What is the guideline regarding the use of colour in data visualisation?
“Use colour when you should, not when you can.”
Why should the number of colours in a chart be used sparingly?
Too much colour can overwhelm the viewer.
What type of colours should be used for unrelated data in charts?
Categorical colours.
How should variations in luminance be used in data visualisation?
To highlight differences in related data.
What can vary the type of chart substitute for?
The use of colours.
Why should variations in background colour be minimised?
Human perception of colour is relative to the object’s surroundings.
