H517 Design, Analysis, & Evaluation Week 6: Marks & Channels (cont’d) Tables and multi-dimensional data

Khairi Reda | [email protected] School of Informacs & Compung, IUPUI Administrativia

• Coming up next week: Project 1 presentations

• 4 min presentation each + 45 sec Q&A (sharp limit!)

• No need to prepare PowerPoint slide, just bring up your vis and show it to class

• You’ll not be allowed to use your own laptop; need to be able to access the vis through a public URL

• Demo the vis, talk about your design process, challenges encountered and how you addressed them

• Audience: ask question, give feedback, critique the vis; always provide constructive comments Last week… Marks Graphical elements in an image

points (0D) lines (1D) areas (2D) volume clouds (3D) Channels (aka Visual Variables) Parameters that control the appearance of marks based on aributes magnitude channels identy channels good for ordered attributes good for categorical attributes

Tamara Munzner Via Miriah Meyer How much longer?

4x

Alex Lex How much larger (area)?

5x

Alex Lex Psychophysics Steven’s Psychological power law

perceived sensation S = In physical intensity Via Miriah Meyer Heer & Bostock, 2010 Discriminability can channel differences be discerned?

Via Miriah Meyer Position Offers very good discriminability

posion Position But this doesn’t extend to 3D!

Perspecve distoron Occlusions Factors affecting accuracy of Length/Position judgement

aligned unaligned stacked bar (unaligned) Separable vs Integral channels

separable channels: can be judged individually integral channels: are viewed holiscally

separable integral

Ware 2004 Based on a slide by Miriah Meyer Chernoff faces Chernoff faces This week

Tables and multi-variate data Key attribute Visualizing Tables Visualizing Tables 1 quantave aribute 1 categorical (key) 2 quantave aributes Visualizing Tables

key attribute

key attribute Don’t use line for categorical aributes!

ok: “Men are taller than bad: “The more male a women (on average)” person is, the taller he is”

ok: “Twelve year olds are ok: “The older a person taller than ten years old” the taller he/she is” Miriah Meyer Arrange Tables Mulple columns/categories

Streit & Gehlenborg, PoV, Nature Methods, 2014 Via Alex Lex Arrange Tables 2 quantave aributes

Y

X

Z Z

X Y

What if we have and want to see more than 2 quantitative attributes at the same time? nine characteristics of Abalone (sea snails)

Wilkinson et al., 2005 Via Miriah Meyer Wilkinson et al., 2005 Via Miriah Meyer Wilkinson et al., 2005 Via Miriah Meyer Parallel Coordinates

V1 V2 V3 V4 V5

10 8 6 4 2 0

Example by Miriah Meyer Parallel Coordinates

posive correlaon straight lines

negave correlaon all lines cross at a single point

Wegman 1990 Via Miriah Meyer Parallel Coordinates

ProtoVis Via Miriah Meyer Do you see any correlation?

Correlaons only visible between neighboring axis pairs:

axis order maers

allow user to reorder axis

Fua 1999 Via Miriah Meyer Hierarchical Parallel Coordinates

Fua 1999 Hierarchical Parallel Coordinates

Instead of showing all points, show a band represenng a cluster:

mean: opaque line

min/max: illustrated by band width with decreasing opacity from mean cluster

Fua 1999 Hierarchical Parallel Coordinates Cluster: lines that share similar shapes. Interacvely varying the similarity threshold allows us to “unpack” clusters

Fua 1999

Radial Layout Star Similar to parallel coordinates, but axes radiate from a common origin

Scotch Whiskies

Via Alex Lex Arrange Tables Arrange Tables as a heatmap

1 2 5 4

5 0 0 1

5 6 1 2

2 1 3 1

4 1 2 1 Arrange Tables Table as a heatmap

1 2 5 4

5 0 0 1

5 6 1 2

2 1 3 1

4 1 2 1 Arrange Tables Table as a heatmap

0 0 Arrange Tables Table as a heatmap

Order is important: Clustering is oen used with heatmaps Next week

Project 1 presentaons