This research examines a design guideline that aims to increase the positive perception of interruptions. The guideline advocates matching the amount of attention attracted by an interruption’s notification method (attentional draw) to the utility of the interruption content. Our first experiment examined a set of 10 visual notification signals in terms of their detection times and established a set of three significantly different signals along the spectrum of attentional draw. Our second experiment investigated matching these different signals to interruption content with different levels of utility. Results indicate that the matching strategy decreases annoyance and increases perception of benefit compared to a strategy that uses the same signal regardless of interruption utility, with no significant impact on workload or performance. Design implications arising from the second experiment as well as recommendations for future work are discussed.

1. Matching Attentional Draw with Utility in Interruption Jennifer Gluck, Andrea Bunt, Joanna McGrenere University of British Columbia CHI 2007 April 30, 2007

13. Primary Task

22. Signals Time (seconds)

24. Study 1 Results: Detection Times High AD signal: Follow Med AD signal: Slow Zoom Low AD signal: Flag

33. Condition Preference

40. Additional Information

43. Study 1: Simple Editor Task

45. Study 1: Structure of a Trial

47. Study 1: Pairwise Comparisons

48. Study 1: Timeouts Main effect of signal (F(2.542,27.961) = 3.630, p = .031, η 2 = .248)

50. Study 2: Interruption Structure

51. Missed-Hints Dialog

52. Study 2 General Annoyance No main effect of condition ( F (2,24) = 2.788, p = .079, η 2 = .166, power = .429)

53. Study 2: Presentation Order Effect F (5,14) = 2.720, p = .064, η 2 = .493

54. Study 2 Interaction Effect F (10,28) = 2..35, p = .068, η 2 = .421

55. Study 2 Hint Duration Main effect of utility ( F (2,36) = 6.839, p = .003, η 2 = .275)

56. Study 2 Workload .143 .115 2.335 Physical Demand .027 .687 .381 Frustration .088 .276 1.347 Perceived Performance .008 .889 .118 Effort .071 .357 1.069 Temporal Demand .004 .945 .057 Mental Demand η 2 p F(2,28) NASA-TLX Factor