A Comparison of Radial and Linear Charts for Visualizing Daily - PowerPoint PPT Presentation

A Comparison of Radial and Linear Charts for Visualizing Daily Patterns Manuela Waldner , Alexandra Diehl, Denis Gracanin, Rainer Splechtna, Claudio Delrieux, Kresimir Matkovic Institute of Visual Computing & Human-Centered Technology, TU Wien, Austria

Radial Charts ? Manuela Waldner 2

Radial Charts “Processing angles is more difficult than processing linear aspects.” [Simkin and Hastie, Journal of the American Statistical Association, 1987] Manuela Waldner 3

Radial Charts “Radial graphs also have the potentially error-prone property that the reader’s eyes must follow one of several concentric rings to map a data point to its value.” [Goldberg and Helfman, SAGE Information Visualization 2011] Manuela Waldner 4

Radial Charts “Using polar rather than Cartesian coordinates has a pleasing aesthetic, while using space more efficiently.” [Heer et al., Commun. ACM 2010] Manuela Waldner 5

Radial Charts “Mapping this circular behavior to a radial diagram is an intuitive concept and mirrors the data appropriately.” [Burch and Weiskopf, Springer Handbook of Human Centric Visualization 2019] Manuela Waldner 6

Radial Charts of Periodical Patterns [Brehmer et al., IEEE TVCG 2019] Manuela Waldner 7

Radial Charts of Periodical Patterns “The participants also reported to like the clock metaphor . Some suggested, however, to visualize only 12 hours at a time for a more intuitive encoding.” [Fuchs et al., ACM CHI 2013] Manuela Waldner 8

Clock Metaphor Manuela Waldner 9

Traffic Accidents https://www.kaggle.com/pavetr/nypdcollisions Manuela Waldner 10

Traffic Accidents Manuela Waldner 11

Rose Chart [Nightingale, 1858] Manuela Waldner 12

Rose Chart [Huang et al., IEEE TVCG 2016] Manuela Waldner 13

Rose Chart Manuela Waldner 14

“Clock Charts” Manuela Waldner 15

Study Design radial linear 2 x 12 1 x 24 Manuela Waldner 16

Study Manuela Waldner 17

Manuela Waldner 18

Untargeted Analysis Manuela Waldner 19

Untargeted Analysis Manuela Waldner 20

Low-Level Tasks Manuela Waldner 21

Low-Level Tasks Manuela Waldner 22

Low-Level Tasks Manuela Waldner 23

Hypothesis Visualizations of daily patterns using a clock-like layout can be interpreted more efficiently by untrained users than using alternative radial or linear charts. Manuela Waldner 24

Untargeted Analysis There are a lot of accidents in the morning There are a lot of accidents in the morning Observation 1 between 8 am and 10 am. Then again in the between 8 am and 10 am. Then again in the Observation 2 afternoon between 1 and 5 pm. afternoon between 1 and 5 pm. Manuela Waldner 25

Locate Maximum Manuela Waldner 26

Locate Maximum accuracy completion time Manuela Waldner 27

Locate Maximum Errors Manuela Waldner 28

Observation Separating charts may attract much more attention to the first chart . Manuela Waldner 30

Locate Time Manuela Waldner 31

Locate Time accuracy completion time Manuela Waldner 32

Locate Time Errors I found it very hard to read initially as I was trying to figure out if the 12pm on the left was for PM or AM, based on it stating AM in the center. This is very confusing. Manuela Waldner 33

Rose Charts [Nightingale, 1858] Manuela Waldner 34

Observation Separate rose charts are difficult to follow . Manuela Waldner 35

Locate Time [Fuchs et al., ACM CHI 2013] Manuela Waldner 36

Observation Locating an hour of a day is more efficient using a continuous, labelled, linear bar chart . Manuela Waldner 37

Read Value Manuela Waldner 38

Read Value accuracy completion time Manuela Waldner 39

Read Value Errors It's pretty decent but I JUST noticed that each bar represents 20 accidents. Before I thought 1 bar = 1 accident because I didn't look closely enough Manuela Waldner 40

Observation Users may not know how to interpret the length of the bars in rose charts. Manuela Waldner 41

Read Value Errors 34 Manuela Waldner 42

Read Value Manuela Waldner 43

Read Value Manuela Waldner 44

Observation Separating radial charts may attract attention to unimportant data points . Manuela Waldner 45

Feedback It is challen engi ging to read. This is simpler er, less pretty or fancy but more effec ecti tive than I prefer seeing a bar graph but the previous one it could be because I am more fam amili liar ar with this. Manuela Waldner 46

Clock Charts? This is really hard rd to look at until you realize that it is showing like a clock. But the data is still diffic icult lt to decipher. Manuela Waldner 47

Clock Charts? ? ? ? Manuela Waldner 48

How to Visualize Daily Patterns? Manuela Waldner 49

Thank you! T 752-N30 Manuela Waldner