Manipulate Views
MIDS W209: Information Visualization
John Alexis Guerra Gómez
| john.guerra[at]gmail.com
| @duto_guerra
Andy Reagan
| andy[at]andyreagan.com |
@andyreagan
https://johnguerra.co/lectures/MIDS_W209_Information_Visualization/10_Manipulate_Views/
Partially based on
slides from Tamara Munzner
What We Are Going to Learn
Manipulate views
Change encodings/parameters
Animations
Interactions
Navigate
Case studies
Manipulate Views
How to Handle Complexity
Three strategies
Change view over time
Facet across multiple views
Reduce items/attributes within single view
And one previous
Derive new data to show within view
Strategies
Change view over time
👈 most obvious one: interaction
Facet
Reduce
Derive
Manipulate
Change Over Time
Change any of the other choices
Encoding itself
Parameters
Arrange: rearrange reorder
Aggregation level, what is filtered...
Interaction entails change
Change Encoding/Parameters
Change Encoding
Made using Tableau
Change Encoding: Vega-Lite
Not so easy in D3 🤷🏼♂️
Change Parameters
Widgets and controls:
Sliders, buttons, radio buttons, checkboxes, dropdowns/comboboxes
Pros:
Clear affordances, self-documenting (with labels)
Cons:
Uses screen space
Design choices:
Separated vs. interleaved
Controls and canvas
Slide inspired by: Alexander Lex, Utah
[Growth of a Nation](http://laurenwood.github.io/)
Case Study: Changing Encoding and Parameters
Hedonometer.org
Line Chart Changes
Change time parameter using brush
Change time parameter using menu
Change encoding of day-of-week using menu
Word Shift Graph Changes
Change time parameter with menu and date picker
Change language parameter with translation toggle
Change position encoding with bar selector
Demo
Animations
Reorder: DataStripes
What: table with many attributes
How: data-driven reordering by selecting column
Why: find correlations between attributes
http://carlmanaster.github.io/datastripes/
Re-Align: LineUp
Stacked bars
Easy to compare
First segment
Total bar
Align to different segment
Supports flexible comparison
[LineUp: Visual Analysis of Multi-Attribute Rankings.Gratzl, Lex, Gehlenborg, Pfister, and Streit. IEEE Trans. Visualization and Computer Graphics (Proc. InfoVis 2013) 19:12 (2013), 2277–2286.]
LineUp
http://vcg.seas.harvard.edu/files/pfister/files/2013_infovis_lineup.mp4
"LineUP" d 3
https://observablehq.com/@john-guerra/lineup
Idiom: Animated Transitions
Smooth interpolation from one state to another
Alternative to jump cuts, supports item tracking
Best case for animation
Staging to reduce cognitive load
Example: animated transitions in statistical data graphics
vimeo.com/19278444
[Animated Transitions in Statistical Data Graphics. Heer and Robertson. IEEE TVCG (Proc InfoVis 2007) 13(6):1240-1247, 2007]
D3 Show Reel
https://bost.ocks.org/mike/miserables/
Animating the Show Reel: Flubber
Collapsible Tree
Tree drilldown/rollup
Zoomable Bar Chart
Tree drilldown/rollup
Value comparison
Zoomable Icicle
Tree drilldown/rollup
Value comparison
Interactions
Selection
Selection: basic operation for most interaction
Design choices
How many selection types?
Interaction modalities
Click/tap (heavyweight) vs. hover (lightweight but not available on most touchscreens)
Multiple click types (shift-click, option-click, etc.)
Proximity beyond click/hover (touching vs. nearby vs. distant)
Application semantics
Adding to selection set vs. replacing selection
Can selection be null?
Example: toggle so nothing selected if click on background
Primary vs. secondary (example: source/target nodes in network)
Group membership (add/delete items, name group, etc.)
Types of Selection
Interval:
Brush 1D
Brush 2D
Individual:
Closest item (hover)
Click to select
Multi:
Shift-click
By similarity (e.g., connection, same state)
Voronoi Maps
Tesselate the canvas
Quickly find the closest point
Highlight
Highlight: change visual encoding for selection targets
Visual feedback closely tied to but separable from selection (interaction)
Design choices: typical visual channels
Change item color
But hides existing color coding
Add outline mark
Change size (example: increase outline mark linewidth)
Change shape (example: from solid to dashed line for link mark)
Unusual channels: motion
Motion: usually avoid for single view
With multiple views, could justify to draw attention to other views
Colombian election results
Interaction Technology
What do you design for?
Mouse and keyboard on desktop?
Large screens, hover, multiple clicks
Touch interaction on mobile?
Small screens, no hover, just tap
Gestures from video/sensors?
Ergonomic reality vs. movie bombast
Eye tracking?
Slide inspired by: Alexander Lex, Utah
Data visualization and the news - Gregor Aisch (37 min)
https://vimeo.com/182590214
I Hate Tom Cruise - Alex Kauffmann (5 min)
https://www.youtube.com/watch?v=QXLfT9sFcbc
Tooltips
Popup information for selection
Hover or click
Can provide useful additional detail on demand
Beware: does not support overview!
Always consider if there’s a way to visually encode directly to provide overview.
"If you make a rollover or tooltip, assume nobody will see it. If it's important, make it explicit."
Gregor Aisch, NYTimes
Responsiveness is Required
Visual feedback: three rough categories
0.1 seconds: perceptual processing
Subsecond response for mouseover highlighting: ballistic motion
1 second: immediate response
Fast response after mouseclick, button press: Fitts’ Law limits on motor control
10 seconds: brief tasks
Bounded response after dialog box: mental model of heavyweight operation (file load)
Scalability considerations
Highlight selection without complete redraw of view (graphics frontbuffer)
Show hourglass for multi-second operations (check for cancel/undo)
Show progress bar for long operations (process in background thread)
Rendering speed when item count is large (guaranteed frame rate)
Navigate
Navigate: Changing Viewpoint/Visibility
Change viewpoint
Changes which items are visible within view
Camera metaphor
Pan/translate/scroll
Rotate
Zoom
Pan/Translate/Scroll
Move up/down
Move sideways
Go to location
Idiom: Scrollytelling
How: navigate page by scrolling (panning down)
Pros:
People don't click, but they scroll
Bottom-up approach
Good for mobile
Cons:
Full-screen mode may lack affordances
Scrolljacking, no direct access
Unexpected behaviour
Continuous control for discrete steps
Eagereyes take on scrollytelling
MBostock's guidelines for scrollytelling
Slide inspired by: Alexander Lex, Utah
Colombian election results
Zoom
Enlarge/shrink world: move camera closer/further
Geometric zoom
: standard, like moving physical object
Semantic zoom
: keep objects same size, but change the scale/viewport
Idiom: Semantic Zooming
Semantic Zoom
Alternative to geometric zoom
Resolution-aware layout adapts to available space
Goal: legible at multiple scales
Dramatic or subtle effects
Visual encoding change
Colored box
Sparkline
Simple line chart
Full chart: axes and tickmarks
[LiveRAC - Interactive Visual Exploration of System Management Time-Series Data. McLachlan, Munzner, Koutsofios, and North. Proc. ACM Conf. Human Factors in Computing Systems (CHI), pp. 1483–1492, 2008.]
LiveRAC
Geometric Zoom
https://observablehq.com/@john-guerra/svg-geometric-zoom
Semantic Zoom
https://observablehq.com/@john-guerra/svg-semantic-zoom
Rotate
Zoom to Constrained
Transition and Animated Navigation
Barchart Race
Interaction Benefits
Interaction Pros
Major advantage of computer-based vs. paper-based visualization
Flexible, powerful, intuitive
Exploratory data analysis: change as you go during analysis process
Fluid task switching: different visual encodings support different tasks
Animated transitions provide excellent support
Empirical evidence that animated transitions help people stay oriented
Interaction Limitations
Interaction has a time cost.
Sometimes minor, sometimes significant
Degenerates to human-powered search in worst case
Remembering previous state imposes cognitive load
Rule of thumb: eyes over memory.
Hard to compare visible item to memory of what you saw
Example: maintaining context/orientation when navigating
Example: tracking complex changes during animation
Controls may take screen real estate.
Or invisible functionality may be difficult to discover (lack of affordances)
Users may not interact as planned by designer.
NYTimes logs show about 90% don’t interact beyond scrollytelling - Aisch, 2016
Manipulate View Case Studies
Colombian Elections
https://johnguerra.co/viz/resultadosSegundaVuelta2018/
Twitter Influentials
https://johnguerra.co/viz/influentials/story/?hashtag=ieeevis2019
Animations on the Web
What We Learned
Manipulate views
Change encodings/parameters
Animations
Interactions
Navigate
Case Studies