Effects of Display Position and Control Space Orientation on User Preference and Performance Presented at CHI2006, April, 2006 Daniel Wigdor Chia Shen Clifton Forlines Ravin Balakrishnan introduce paper title Co-authors MERL & DGP Brief summary richness in paper (though ugly without colour)

Problem Watch this week!

Motivation

Issues Display Position Control Space Orientation Define terms Example: using mouse with screen in front of you Degrees vs letters Control Space Orientation

Hemholtz (1866), Stratton (1897): prism glasses Cunningham (1989) Related Work HCI: Nacenta et al. (2005) Psychology: Hemholtz (1866), Stratton (1897): prism glasses Cunningham (1989) Cunningham & Welch (1994) Prism glasses remove retinal inversion Cunningham 1: (insert thoughts!) Cunningham 2: (insert thoughts!)

Performance penalties Recommend: Our Goals Find: Preferred: Display position(s) Control orientation(s) for each position Optimal: Control orientation for each position Performance penalties Recommend: Ideal display position(s) Ideal control orientation(s) Mouse seems to solve orientation problem

Two Experiments: Preference, Performance Screen on wheels Pen based input device Imagine wacom tablet done virtually

Two Experiments: Preference, Performance Screen on wheels Pen based input device Imagine wacom tablet done virtually

Task Docking task: Blue target on to red dock

Study 1: All About Preference Setup: Perform task at all 8 display positions Participant sets control orientation Measure: Task time & error rate Control orientation chosen by the participant Participants’ preferred display position Tells us: Optimal display position Preferred control orientation for each position Performance at preferred control orientation

+ Design 8 participants (all right handed) 8 display positions 40 trials per position Participant-set control orientation + Position orient reference frame themselves

Results: Display Position Preference Participant Most Preferred Least Preferred 1 N S 2 NE 3 NE & NW 4 NW 5 6 SW 7 SE & S 8 6 of 8 participants prefer NE or NW position

Results: Control Orientation Preference Each colour is a participant

Results: Control Orientation Preference North (in front of the user) tight spread, but not all north

Results: Control Orientation Preference 10:00

Study 2: All About Performance Setup: Perform task at all 8 display positions For each position, perform task at 8 control orientations Measure: Task time & error rate Drag paths Tells us: Optimal control orientation for each position Penalty for not meeting optimal Display position and control orientation for shared displays Avoid single user bias / ‘sweet spots’

+ Design 8 participants (all right handed) 4 display positions each (8 total) 4 fixed control orientations each (8 total) 80 trials per position +

Results: Performance Explain graph

Results: Performance Explain graph

Screen North

Screen North

Screen North

Screen North

Results: Performance Interesting results Users don’t know what they’re talking about!

Results: Performance Green cases: optimal was within range selected by users. Red cases: wasn’t within range.

Design Recommendations 1 & 2 S SE E NE N NW W SW

Design Recommendations 1 & 2 S 53% SE 32% E 62% NE 46% N NW 36% W 41% SW 38%

Design Recommendations 1 & 2 1 & 3 S 53% SE 32% E 62% NE 46% N NW 36% W 41% SW 38%

Design Recommendations 1 & 2 1 & 3 S 53% 32% SE 38% E 62% 18% NE 46% 75% N NW 36% W 41% SW

Design Recommendations 1 & 2 1 & 3 1,2,3 S 53% 32% SE 38% E 62% 18% NE 46% 75% N NW 36% W 41% SW Least preferred position is best!

Design Recommendations 1 & 2 1 & 3 1,2,3 S 53% 32% SE 38% E 62% 18% NE 46% 75% N NW 36% W 41% SW Least preferred position is best!

Design Recommendations 1 & 2 1 & 3 1,2,3 1,2,3,4 S 53% 32% SE 38% E 62% 18% NE 46% 75% N NW 36% W 41% SW

Design Recommendations 1 & 2 1 & 3 1,2,3 1,2,3,4 S 53% 32% 183% SE 38% 273% E 62% 18% NE 46% 75% N NW 36% W 41% SW

Acknowledgements Dr. Helen Cunningham Experimental participants John Barnwell Edward Tse CHI meta-reviewer ARDA

Questions?